The Hacker's Encyclopedia 1998/hackers_encyclopedia.iso/etc/misc/acronyms.lst

File List | 2003-06-11 | 131.4 KB | 3,366 lines

2D      2-Dimensional
3D      3-Dimensional
3M      Minnesota Mining and Manufacturing
4GL     Fourth Generation Language
4H      Head, Heart, Hands, Health
4WD     Four wheel Drive (see also FWD)
A       Aftermath
AA      Affirmative Action committee
AA      Alcoholics Anonymous
AA      Antiaircraft Artillery
AA      Associate in Accounting
A&A     Astronomy and Astrophysics [Space]
AA      Automobile Association [England]
AAA     American Automobile Association
AAAL    American Academy of Arts and Letters
AAAS    American Association for the Advancement of Science
AAII    American Association of Individual Investors
AAMSI   American Association for Medical Systems Informatics
AAO     Anglo-Australian Observatory [Space]
AAP     Affirmative Action Program
AARC    Anglo-American Cataloging Rules
AARN    Australian Academic Research Network [Networking]
AARP    American Association of Retired Persons
AAS     American Astronomical Society [Space]
AAVSO   American Association of Variable Star Observers [Space]
AB      ABle seaman
ABA     American Bar Association
ABA     American Basketball Association
ABA     American Booksellers Association
ABBR    ABBReviation
ABC     American Broadcasting Company [Corporate name]
AC      Alternating Current (ac, see also DC)
AC      Ante Christum (before Christ)
AC      Ante Cibum (before meals)
ACAA    Agricultural Conservation and Adjustment Administration
ACAWS   Advisory, Caution, And Warning System
ACBL    American Contract Bridge League
ACC     Argonne Code Center
ACCS    Army Command and Control System
ACD     Automatic Call Distributor [Telephony]
ACE     Advanced Composition Explorer [Space]
ACE     Advanced Computing Environments [Corporate name]
ACE     Automatic Calibration and Equalization
ACHEFT  Automated ClearingHouse Electronic Funds Transfer
ACK     ACKnowledge
ACL     Advanced Cmos Logic
ACLU    American Civil Liberties Union
ACM     Association for Computing Machinery
ACRV    Assured Crew Return Vehicle (or) Astronaut Crew Rescue Vehicle [Space]
ACS     Advanced Communications System
ACSE    Association Control Service Entity (ISO/CCITT layer 7)
ACT     Action for Children's Television (in Cambridge, MA)
ACT     American Conservatory Theater
ACTS    Advanced Communications Technology Satellite
ACTS    Automatic Coin Telephone Service [Telephony]
ACU     Alarm Control Unit
ACU     Automatic Call Unit [Telephony]
ACW     Alternating Continuous Waves
AD      After Date
A/D     Analog to Digital converter (see ADC)
AD      Anno Domini (in the year of our Lord)
AD      Application Development
Ad Astra        To the stars [Latin, Space]
ADAP    Alzheimer's disease-associated protein
ADAP    American Discount Auto Parts [Corporate name]
ADB     A DeBugger
ADB     Apple Desktop Bus
ADC     Analog to Digital Converter
ADCI    Automatic Display Call Indicator
AD&D    Advanced Dungeons & Dragons
ADF     Automatic Direction Finder
ADM     ADMiral
ADP     Adenosine Di-Phosphate
ADP     Administrative Data Processing
ADP     Advanced Data Processing
ADPCM   Pulse Code Modulation with Adaptive Quantization
ADS     Application Development System
ADSR    Attack Decay Sustain Release
ADT     Abstract Data Type
ADT     Atlantic Daylight Time
AE      Application Execution
AEA     American Electronics Association
AEC     Atomic Energy Commission
AEF     American Expeditionary Force (see BEF)
AEGIS   Advanced Electronic Guidance and Instrumentation System
AF      Adventures in Fantasy
AF      Air Force
AF      Audio Frequency
AFADS   Automatic Force Adjustment Data System
AFATDS  Advanced Field Artillery Tactical Data System
AFB     Air Force Base
AFC     American Football Conference
AFC     Automatic Flight Control
AFC     Automatic Frequency Control
AFCAC   Air Force Computer Acquisition Center
AFCC    Air Force Communications Command
AFGE    American Federation of Government Employees
AFIPS   American Federation of Information Processing Societies
AFL     American Federation of Labor
AFL     American Football League
AFLCIO  American Federation of Labor and Congress of Industrial Organizations
AFNOR   Association Francaise de NORmalization
AFP     Appletalk Filing Protocol
AFS     Andrew File System
AFSC    Air Force Systems Command
AFSCME  American Federation of State, County and Municipal Employees
AFTRA   American Federation of Television and Radio Artists
AG      Adjutant General
AG      Arcade Game
AG      Attorney General
AGCT    Army General Classification Test
AGN     Active Galactic Nucleus [Space]
AHL     American Hockey League
AHQ     Air HeadQuarters
AI      Artificial Intelligence
AIAA    American Institute of Aeronautics and Astronautics [Space]
AIC     Automatic Intercept Center
AID     Agency for International Development
AIDDE   Ames' Interactive Dynamic Display Editor
AIDS    Acquired ImmunoDeficiency Syndrome
AIOD    Automatic Identification Outward Dialing
AIS     Automatic Intercept System
AIX     Advanced Interactive eXecutive (IBM's name for UNIX)
AJ      Astronomical Journal [Space]
AK      Alaska
AKA     Also Known As
AL      Alabama [US state postal designation]
AL      American League (baseball)
ALA     American Library Association
ALA     Automobile Legal Association
ALBM    Air-to-Land Ballistic Missile
ALC     Automatic Load Control
ALGOL   ALGOrithmic Language
ALIT    Automatic Line Insulation Testing [Telephony]
ALPO    Association of Lunar and Planetary Observers [Space]
ALS     Advanced Launch System [Space]
ALU     Arithmetic Logic Unit
A&M     Agricultural and Mechanical
AM      Amplitude Modulation
AM      Ante Meridiem (before noon)
AMA     American Medical Association
AMA     Automatic Message Accounting [Telephony]
AMARC   Automatic Message Accounting Recording Center
AMBA    Association of Master of Business Administration
AMC     Albany Medical College
AMC     American Motors Corporation(?) [Corporate name]
AMC     Appalachian Mountain Club
AMD     Advanced Micro Devices [Corporate name]
AMEX    AMerican EXpress [Corporate name]
AMI     Alternate Mark Inversion (see also NRZ, NRZI, B8ZS)
AMORC   Ancient Mystic Order Rosae Crucis
AMP     Adenosine MonoPhosphate
AMPAS   Academy of Motion Picture Arts and Sciences
AMPAS   Acedemy of Motion Picture Arts and Sciences
AMRAAM  Advanced Medium Range Air-To-Air Missile
AMROC   American Rocket Company [Space]
AMSAT   radio AMateur SATellite corp.
AMU     Atomic Mass Unit
AMVET   AMerican VETeran
ANA     American Nurses Association
ANAC    Automatic Number Announcemnt Circuit [Telephony]
ANC     All Number Calling [Telephony]
ANC     Army Nurse Corps
ANDF    Architecture-Neural Distribution Format
ANF     Automatic Number Forwarding [Telephony]
ANG     Air National Guard
ANI     Automatic Number Identification (see also: CLID) [Telephony]
ANL     Argonne National Laboratory
ANOVA   ANalysis Of VAriance
ANPA    American Newspaper Publishers Association
ANSI    American National Standards Institute
ANZUS   Australia, New Zealand, United States
AO      Account Of
AOA     Abort Once Around [NASA, Shuttle]
AOA     Abort Once Around (Shuttle abort plan) [Space]
AOL     Absent Over Leave (see AWOL)
AOS     Academic Operating System
AOS     Alternate Operator Service [Telephony]
A/P     Accounts Payable
AP      Additional Premium
AP      All Points
AP      Associated Press [Corporate name]
APA     All Points Addressable
APA     American Psychological Association
APB     All Points Bulletin
APDA    Apple Programmers and Developers Association
API     Application Programming Interface
APICS   American Production and Inventory Control Society
Ap.J    Astrophysical Journal [Space]
APL     A Programming Language
APL     acute promyelocytic leukemia [Disease]
APO     Alpha Phi Omega, service fraternity
APO     Army Post Office
APP     Applications Portability Profile
APPC    Advanced Peer-to-Peer Communications
APR     Annual Percentage Rate (as in loan interest)
APSE    Ada Programming Support Environment
APU     Auxiliary Power Unit [Space]
AQ      Accumulator-Quotient register
A/R     Accounts Receivable
AR      Address Register
AR      Arkansas
ARC     AIDS-related complex
ARC     American Red Cross
ARC     Ames Research Center (NASA) [Space]
ARCNET  Attached Resource Computer local area NETwork
ARO     After Receipt of Order
ARP     Address Resolution Protocol
ARPA    Advanced Research Projects Agency (of the DoD, see DARPA)
ARPANET ARPA (q.v.) NETwork
ARRL    Amateur Radio Relay League
ARV     American Revised Version
AS      Anglo-Saxon
ASA     Acetyl Salicylic Acid
ASAP    As Soon As Possible
ASC     Accredited Standards Committee
ASCAP   American Society of Composers, Authors, and Publishers
ASCC    Automatic Sequence-Controlled Calculator
ASCII   American Standard Code for Information Interchange
ASDIC   Anti-Submarine Detection Investigation Committee (British for sonar)
ASDSP   Application-Specific Digital Signal Processor
ASG     Automated Sciences Group
ASHRAE  Amer. Soc. of Heating, Refrigerating and Air-cond. Engineers, inc.
ASIC    Application Specific Integrated Circuit
ASME    American Society of Mechanical Engineers
ASN     Abstract Syntax Notation One (ISO/CCITT ASN.1)
ASP     Aggregated Switch Procurement
ASRM    Advanced Solid Rocket Motor [Space]
ASSR    Autonomous Soviet Socialist Republic
AST     Atlantic Standard Time
ASV     American Standard Version
AT      Atlantic Time
ATA     Automatic Trouble Analysis
ATACC   Advanced Tactical Air Command Central
ATB     Advanced Technology Bomber (stealth bomber)
ATC     Air Traffic Control
ATDRS   Advanced Tracking and Data Relay Satellite [Space]
ATF     Advanced Technology Fighter
ATIS    Atherton Tools Interface Specification
ATLAS   Atmospheric Laboratory for Applications and Science [Space]
ATM     Amateur Telescope Maker [Space]
ATM     Asynchronous Transfer Mode
ATM     Automatic Teller Machine
ATO     Abort To Orbit [NASA, Shuttle]
ATO     Abort To Orbit (Shuttle abort plan) [Space]
ATOMS   AT&t Optimized Materials Simulator
ATP     Adenosine TriPhosphate
ATPCO   Airline Tariff Publishing COmpany
AT&T    American Telephone & Telegraph [Corporate name]
ATT     American Telephone & Telegraph (normally written AT&T when seperate)
ATTIS   American Telephone and Telegraph Information Systems [AT&T] (Division)
ATV     All Terrain Vehicle
AU      Astronomical Unit (93,000,000 miles) [Space]
AU      Astronomical Unit [Space]
AUI     Attachment Universal Interface
AURA    Association of Universities for Research in Astronomy [Space]
AUS     Army of the United States
AUTODIN AUTOmatic DIgital Network
AUTOVON AUTOmatic VOice Network
AV      AudioVisual
AVLIS   Atomic Vapor Laser Isotope Separation
AWACS   Airborne Warnings And Control Systems
AWEA    American Wind Energy Association
AWK     al Aho, peter Weinberger, brian Kernighan (pattern scanning language)
AWOL    Absent WithOut Leave (also Absent Without Official Leave) (see AOL)
AW&ST   Aviation Week and Space Technology (a.k.a. AvLeak) [Space]
AXAF    Advanced X-ray Astrophysics Facility [Space]
AZ      Arizona
B       Book
B8ZS    Binary 8 Zero Substitution (see also NRZ, NRZI, AMI)
BA      Bachelor of Arts
BACH    Business Alliance for Commerce in Hemp
BAFO    Best And Final Offer
BARRNet Bay Area Regional Research Network (SF Bay Area)
BASIC   Beginner's All-purpose Symbolic Instruction Code
BATSE   Burst And Transient Source Experiment (on GRO) [Space]
BB      Bases on Balls
BB      Best of Breed
BB      Bunnies and Burrows
BBA     Bachelor of Business Administration
BBB     Better Business Bureau
BBC     British Broadcasting Corporation
BBL     Barrel
BBN     Bolt, Beranek, and Newman, Inc. [Corporate name]
BBXRT   Broad-Band X-Ray Telescope (ASTRO package) [Space]
BC      Battlecars
BC      Before Christ
BC      British Columbia
BC/BS   Blue Cross/Blue Shield
BCD     Bad Conduct Discharge
BCD     Binary Coded Decimal
BCDIC   Binary Coded Decimal Interchange Code
BCE     Before the Common Era (substitute for BC)
BCNU    Be Seeing You [Net jargon]
BCP     Byte Controlled Protocols
BCPL    Basic Combined Programming Language
BCS     Bachelor of Commercial Science
BCS     Binary Compatibility Standard
BCS     Boston Computer Society
BCS     British Computer Society
BD      Bachelor of Divinity
BD      Bank Draft
BD      Bills Discounted
BD&D    Basic Dungeons & Dragons
BDF     Binary Distribution Format
BDT     Billing Data Transmitter
BE      Bill of Exchange
BEF     British Expeditionary Force (see AEF)
BELCORE BELL COmmunications REsearch
BEM     Bug Eyed Monster
BEM     Bug-Eyed Monster [Space]
BENELUX BElgium, NEtherlands, and LUXembourg
BER     Bit Error Rate
BERT    Bit Error Rate Test
BEST    Borland Enhanced Support and Training
BF      Brought Forward
BFA     Bachelor of Fine Arts
BFD     Bristol (RI) Fire Department (probably typical of any town starting "B")
BH      Black Hole [Space]
BH      Boot Hill
BHP     Brake HorsePower
BICS    Building Industry Consulting Services [Telephony]
BID     Bis In Die (twice a day)
BIMA    Berkeley Illinois Maryland Array [Space]
BIOS    Basic Input Output System
BIS     Business Information System
BISDN   Broadband ISDN (q.v.) [Telephony]
BiSync  Binary Synchronous Communications (BSC is preferred) [IBM]
Bit     BInary digiT
BITNET  Because It's Time Network
BLAST   BLocked ASynchronous Transmission
BLERT   BLock Error Rate Test
BLF     Busy Lamp Field [Telephony]
BLT     Bacon, Lettuce, and Tomato (sandwich)
BLT     BLock Transfer [Instruction]
BLT     Branch Less Than [Instruction]
BM      Basal Metabolism
BM      Bowel Movement
BMA     Bank Marketing Association
BMEWS   Ballistic Missile Early Warning
BMO     Ballistic Missile Office
BMOC    Big Man On Campus
BMR     Basal Metabolism Rate
BNC     Bayonet Neill Concelman (connector) [Electronics] (see also TNC)
BNF     Bachus-Naur Form
BO      Body Odor
BO      Branch Office
BO      Buyer's Option
BOC     Bell Operating Company
BOD     Board Of Directors
BOF     Birds Of a Feather
BOM     Bill Of Materials
BOOTP   Bootstrap Protocol [Internet]
BOQ     Bachelor Officers' Quarters
BOS     Business Office Supervisor
BOSIX   Biin Open System Interface eXtension
BP      Blood Pressure
BP      British Petroleum
BP      British Pharmacopoeia
BPI     Bits Per Inch
BPL     Boston Public Library
BPL     Branch if PLus [Instruction]
BPOE    Benevolent and Protective Order of Elks
BPS     Bits Per Second
BR      Bills Receivable
BR      British Rail
BRA     Boston Redevelopment Authority
BRI     Basic Rate Interface (ISDN) [Telephony]
BRIEF   Basic Reconfigurable Interactive Editing Facility
BRL     army Ballistic Research Laboratory
BRS     Bibliographic Retrieval Service
BS      Bachelor of Science
BS      Bill of Sale
BSA     Birmingham Small Arms
BSA     Boy Scouts of America
BSc     Bachelor of SCience
BSC     Binary Synchronous Communications (also sometimes BiSync) [IBM]
BSD     Berkeley Software Distribution
BSN     Bachelor of Science in Nursing
BSS     Block Started by Symbol
BSTJ    Bell System Technical Journal
BT      British Telecom
BTAM    Basic Telecommunications Access Method [IBM]
BThU    British Thermal Unit (BTU {q.v.} is preferred)
BTL     Bell Telephone Laboratories
BTO     Bachman Turner Overdrive
BTU     British Thermal Unit
BTW     By The Way [Net jargon]
BU      Boston University
BUF     B-52 bomber ("Big Ugly Fellow") [USAF]
BV      Blessed Virgin
BWI     Baltimore-Washington International (airport)
BWI     British West Indies
BX      Base eXchange (see also PX)
c       centi- (metric 1/100)
C       programming language (successor to B, which was based on BCPL)
CA      California
CA      Chartered Accountant
CA      Chief Accountant
CA      Chronological Age
CA      Collision Avoidance (as in CSMA/CA (q.v.))
CAB     Civil Aeronautics Board
CACM    Communications of the Association for Computing Machinery
CAD     Computer Aided Design (sometimes seen as CAD/CAM)
CAD     Computer Aided Dispatching
CAE     Common Applications Environment
CAE     Computer Aided Engineering
CAI     Computer Aided Instruction
CAIS    Common Apse Interface Specification
CALS    Computer-aided Acquisition and Logistics Support
CAM     Computer Aided Management
CAM     Computer Aided Manufacturing (sometimes seen as CAD/CAM)
CAM     Content Addressable Memory
CAMA    Centralized Automatic Message Accounting [Telephony]
CAMP    Campaign Against Marijuana Planting
CAP     Civil Air Patrol
CAP     Columbia Appletalk Package
CAR     Contents of the Address part of the Register (LISP)
CARE    Committee on American Relief in Europe
CARP    California Air Resources Board
CASE    Computer Aided Software Engineering
CASSIS  Classification and Search Support Information System
CAT     Computer-Aided Tomography
CATIS   Common Applications and Tools Integration Services
CATV    Common Antenna TeleVision
CATV    Community Antenna TeleVision
CAVU    Ceiling And Visibility Unlimited
CB      Citizens Band radio
CBC     Canadian Broadcasting Corporation
CBD     Cash Before Delivery
CBD     Commerce Business Daily
CBEMA   Computer & Business Equipment Manufacturers Association
CBR     Chemical, Biological, Radiological warfare
CBS     Columbia Broadcasting System [Corporate name]
CBW     Chemical and Biological Warfare
CC      C (language) Compiler
CC      Carbon Copy
CCA     Computer Corporation of America [Corporate name]
CCAFS   Cape Canaveral Air Force Station [Space]
CCC     Canadian Committee on Cataloging
CCC     Civil(ian) Conservation Corps
CCC     Command, Control, and Communications (sometimes C^3)
CCC     Concourse Computer Center [MIT]
CCCCM   CCC CounterMeasures (sometimes C^3CM)
CCCI    Command, Control, Communications, and Intelligence
CCD     Charge Coupled Device (see CID)
CCD     Charge-Coupled Device [Space]
CCDS    Centers for the Commercial Development of Space [Space]
CCF     Hundred Cubic Feet
CCI     Computer Carrier Interrupt
CCI     Computer Consoles, Incorporated
CCIP    Continuously Computed Impact Point
CCIRN   Coordinating Committee for Intercontinental Research Networking
CCIS    Common Channel Interoffice Signaling [Telephony]
CCITT   Comite' Consultatif International Telegraphique et Telephonique
CCITT   Consultative Committee on International Telephony and Telegraphy
CCITT   International Telegraph and Telephone Consultative Committee
CCR     Commitment, Concurrency, and Recovery
CCR     Creedence Clearwater Revival [Music]
CCRI    Community College of Rhode Island [Corporate name]
CCRP    Continuously Computed Release Point
CCS     Hundred Call Seconds [Telephony]
CCS7    Common Channel Signalling (version #7) [Telephony, AT&T]
CCSA    Common Control Switching Arrangement [Telephony]
CCTA    Central Computer and Telecommunications Agency
CCTV    Closed Circuit TeleVision
CD      Carrier Detect (properly DCD (q.v.)) (EIA RS-232-C)
CD      Certificate of Deposit
CD      Civil Defense
CD      Collision Detection (as in CSMA/CD (q.v.))
CD      Compact Disk
CDA     Call Data Accumulator
CDA     Compound Documents Architecture
CDC     Centers for Disease Control
CDC     Control Data Corporation, Inc. [Corporate name]
CDEV    Control panel DEVice
CDIAC   Carbon Dioxide Information Analysis Center
CDO     Community Dial Office
CDR     CommanDeR
CDR     Contents of the Decrement part of the Register (LISP)
CD-ROM  Compact Disk Read Only Memory
CD-ROM  Compact Disk Read-Only Memory [Space]
CDSF    Commercially Developed Space Facility
CDT     Central Daylight Time
CDU     Control Display Unit
CE      Chemical Engineer
CE      Civil Engineer
CE      Common Era (substitute for AD)
CE      Corps of Engineers
CE      Customer Engineer (see also FE, SE)
CEA     Commissariat a l'Energie Atomique (Frenc Atomic Energy Commision)
CEA     Council of Economic Advisors
CEA     County Education Authority
CEC     Commission of the European Communities
CED     Committee for Economic Development
CELSS   Controlled Ecological Life Support System [Space]
CENS    Centre d'Etudes Nucleaires de Seclay
CENTO   CENtral Treaty Organization
CEO     Chief Executive Officer
CERFnet California Education and Research Federation Network
CERN    European Organization for Nuclear Research
CERN    organisation (formerly Conseil) Europeenne pour la Recherche Nucleaires
CERT    Computer Emergency Response Team
CEVI    Common Equipment Voltage Indicator
CF      Carry Forward
CF      Coin First (payphone) [Telephony]
CF      Cystic Fibrosis [Disease]
CFA     Center For Astrophysics [Space]
CFC     Chloro-FluoroCarbon [Chemical]
CFC     Combined Federal Campaign
CFD     Computational Fluid Dynamics
CFHT    Canada-France-Hawaii Telescope [Space]
CFI     Cost, Freight, and Insurance
CFL     Canadian Football League
CFO     Chief Financial Officer
CG      Coast Guard
CG      Commanding General
CGA     Color Graphics Adapter
CGCT    Compagnie Generale de Constructions Telephoniques
CG&E    Cincinnati Gas & Electric
CGE     Compagnie Generale d'Electricite
CH      Cardboard Heroes
CH      ClearingHouse
CH      CourtHouse
CH      Customs House
CHA     Champions
CHAP    CHAnnel Processor
CHARA   Center for High Angular Resolution Astronomy [Space]
CHI     Chill:  Adventures into the Unknown
CHOTS   Corporate Headquarters Office Technology System
CHP     California Highway Patrol
CI      Cubic Inches
CIA     Central Intelligence Agency [US Government]
CIA     Culinary Institute of America (Hyde Park, NY)
CIC     Carrier Identification Codes [Telephony] (10XXX codes)
CIC     Committee on Institutional Cooperation
CIC     Coordination and Information Center [CSNet]
CICA    Competition in Contracting Act
CICS    Customer Information Control System [IBM]
CID     Caller ID [Telephony] (see also: CLID, ANI)
CID     Central Institute for the Deaf
CID     Charge Injection Device (see CCD)
CID     Computer Integrated Design
CIDIN   Common Icao Data Interchange Network
CIM     Computer Integrated Manufacturing
CIO     Chief Information Officer
CIRRIS  Cryogenic InfraRed Radiance Instrument for Shuttle [Space]
CISC    Complex Instruction Set Computer
Cislunar        The space between the Earth and the Moon
CIT     California Institute of Technology
CIT     Case Institute of Technology (part of CWRU, Cleveland, OH)
CIT     Circumstellar Imaging Telescope [Space]
CLASP   Comprehensive Logistics Automated Support Program
CLASS   Custom Local Area Signaling Service [Telephony]
CLI     Command Line Interpreter
CLID    Calling Line ID [Telephony] (see also: CID, ANI)
CLNP    Connectionless-mode Network Protocol
CLNS    Connectionless-mode Network Service
CLR     Combined Line and Recording
CLRC    Circuit Layout Record Card
CLU     Chartered Life Underwriter
CLUT    Color LookUp Table
cm      centimeters
CM      Command Module (Apollo spacecraft) [Space]
CM      Congregation of the Mission
CMC     Communication Machinery Corp.
CMD     Centralized Message Distribution
CMIP    Common Management Information Protocol
CMIS    Common Management Information Services
CML     Current Model Logic
CMMU    Cache/Memory Management Unit
CMOS    Complementary Metal Oxide Semiconductor (see MOS)
CMOT    Common Management Information Services and Protocol Over TCP/IP
CMRR    Common Mode Rejection Ratio
CMS     Circuit Maintenance System
CMSgt   Chief Master Sergeant
CMU     Carnegie-Mellon University
CMYK    Cyan, Magenta, Yellow, blacK
CN      Canadian National [Corporate name, Railroading]
CN/A    Customer Name / Address [Telephony]
CNI     Common Network Interface [Telephony, AT&T] (Department of AT&T)
CNN     Cable News Network
CNO     Carbon-Nitrogen-Oxygen [Space]
CNO     Chief of Naval Operations
CNR     Canadian National Railways
CNR     Carrier to Noise Ratio
CNRI    Corporation for National Research Initiatives
CNRS    Centre National de la Recherche Scientifique (French National Center for Scientific Research)
CNS     Central Nervous System
CNSR    Comet Nucleus Sample Return [Space]
CO      Cash Order
CO      Central Office [Telephony]
CO      Colorado
CO      Commanding Officer
CO      Conscientious Objector
C/O     in Care Of
COB     Close Of Business
COBE    COsmic Background Explorer [Space]
COBOL   COmmon Business Oriented Language
COC     Call of Cthulhu
COCOT   Customer Owned, Coin Operated Telephone [Telephony]
COD     Collect On Delivery; Cash On Delivery
CODEC   COder-DECoder
COER    Central Office Equipment Report
COLA    Cost-Of-Living Allowance
COM     Computer Output (on) Microfiche
COM     Computer Output (on) Microfilm
COMAS   Central Office Maintenance and Administration System
COMM    Communications
COMPACT COMmercial Product ACquisition Team
COMPTEL COMPton TELescope (on GRO) [Space]
COMSAT  Communications Satellite [Space]
CONACYT Consejo Nacional de Cienca Y Tecnologia (Mexican National Council of Science and Technology)
CONS    Connection-Oriented Networking Service
CONS    Connection-Oriented Networking Session
CONS    CONStruct (LISP)
CORE    COntrolled Requirement Expression
CORN    COmputer Resource Nucleus
COS     Corporation for Open Systems
COSINE  Cooperation for Open Systems Interconnection Networking in Europe
COSMIC  COmmon System Main InterConnecting frame
COSMIC  COmputer Software Management and Information Center
COSMOS  COmputer System for Mainframe OperationS
COSTAR  Corrective Optics Space Telescope Axial Replacement [Space]
COT     Card Or Tape (NCR)
CP      Campus Police (MIT, others probably too)
CP      Canadian Pacific
CP      Chemically Pure
CP      Command Post
CP      Command Processor
CP      CoPy
CP      the Canadian Press
CPA     Certified Public Accountant
CPE     Customer Premises Equipment
CPE     Customer Provided Equipment
CPFF    Cost Plus Fixed Fee
CPI     Characters Per Inch
CPI     Common Programming Interface
CPL     Combined Programming Language
CPM     Control Program for Microcomputers (sometimes CP/M)
CPM     Control Program Monitor (sometimes CP/M)
CPO     Chief Petty Officer
CPO     Chief Post Office
CPR     Canadian Pacific Railway
CPS     Characters Per Second
CPSR    Computer Professionals for Social Responsibility
CPT     CaPTain
CPU     Central Processing Unit
CPW     Certified Public Weigher
CQ      Change of Quarters
CR      Carriage Return (ASCII 15 octal)
CRA     Cambridge Redevelopment Authority
CRAF    Comet Rendezvous / Asteroid Flyby [Space]
CRAM    Card Random Access Memory (NCR, but maybe others)
CRC     Chemical Rubber Company
CRC     Cyclic Redundancy Check
CREG    Concentrated Range Extension with Gain
CREN    The Corporation for Research and Educational Networking (merge of BITNET and CSNet)
CRRES   Combined Release / Radiation Effects Satellite [Space]
CRRES   Combined Release and Radiation Effects Satellite [NASA]
CRT     Cathode Ray Tube (also generic reference to a terminal)
CRTC    Canadian Radio-television and Telecommunications Commission
C&S     Chivalry & Sorcery
CS      Civil Servant
CS      Computer Science; Computing Science
CS      County Seat
CSA     Confederate States of America
CSAB    Computing Sciences Accreditation Board
CSACS   Centralized Status, Alarm and Control System
CSC     Computer Sciences Corporation
CSDC    Circuit Switched Digital Capability
CSF     Critical Success Factor
CSI     Commercial Systems Integration
CSIS    Canadian Security and Intelligence Service
CSL     Coin Supervising Link
CSM     Command and Service Module (Apollo spacecraft) [Space]
CSM     Command Sergeant Major
CSMA    Carrier Sense Multiple Access
CSMA/CA Carrier Sense Multiple Access with Collision Avoidance
CSMA/CD Carrier Sense Multiple Access with Collision Detection
CSNET   Computer + Science Network (merged with BITNET to make CREN)
CSO     Central Services Organization
CSOC    Consolidated Space Operations Center (at Colorado Springs)
CSP     Control Switching Point
CSR     Control and Status Register
CSR     Customer Service Representative [Telephony]
CSRG    Computer Systems Research Group
CSRS    civil Service Retirement System
CSS     Customer Switching System
CST     Central Standard Time
CSU     Channel Service Unit
CT      Central Time
C&T     Communications & Tracking [Space]
CT      Connecticut
CTC     Canadian Transport Commission
CTC     Centralized Traffic Control [Railroading]
CTD     Computing and Telecommunications Division
CTIO    Cerro Tololo Inter-american Observatory
CTIO    Cerro Tololo Interamerican Observatory [Space]
CTNE    Compania Telefonica Nacional de Espana
CTS     Clear To Send (EIA RS-232-C)
CTS     Compatible Timesharing System
CTV     Canadian TeleVision network
CU      Close-Up
CUA     Common User Access
CUL     See You Later [Net jargon]
CV      Curriculum Vitae
CW      Car Wars
CW      Chemical Warfare
CW      Child Welfare
CW      Churchwarden
CW      Churdwarden
CW      Continuous Wave
CWO     Cash With Order
CWO     Chief Warrant Officer
CWRU    Case Western Reserve University
CXI     Common X-windows Interface
CY      Calendar Year
CYO     Catholic Youth Organization
CZ      Canal Zone
D       Depth
DA      Days after Acceptance
DA      Department of Agriculture
DA      Deposit Account
D/A     Digital to Analog converter
DA      Directory Assistance (/C = computerized, /M = Microfilm) [Telephony]
DA      District Attorney
DA      Don't Answer [Telephony] (may be more general)
DAC     Digital to Analog Converter
DA/C    Directory Assistance/Computerized
DACCS   Digital Access Cross Connect System [Telephony] (suspect, see DACS)
DACS    Digital Access Cross-connect System [Telephony]
DAD     Draft ADdendum
DAG     Directed Acyclic Graph
DAL     Dedicated Access Line [Telephony]
DA/M    Directory Assistance/Microfilm
DAP     Division Advisory Panel (of NSF (q.v.) DNCRI (q.v.))
DAR     Daughters of the American Revolution
DARE    Drug Abuse Resistance Education
DARPA   Defense Advanced Research Projects Agency (of the DoD, see also ARPA)
DASD    Direct Access Storage Device
DAT     Digital Audio Tape
DATA    Defense Air Transport Administration
DAV     Disabled American Veterans
DB      DataBase
db      decibel(s)
dba     doing business as
DBF     DBase Format
DBME    DataBase Managment Environment
dbms    DataBase Management System (rdbms for Relational ...)
DBRAD   Data Base Relational Application Directory
DC      Direct Current (dc, see also AC)
DC      District of Columbia
DCA     Defense Communications Agency
DCA     Distributed Communication Architecture
DCA     Document Content Architecture
DCC     Descriptive Cataloging Committee
DCCO    Defense Commercial Communications Office
DCD     Data Carrier Detect (sometimes CD (q.v.)) (EIA RS-232-C)
DCE     Data Communication Equipment
DCL     Digital Command Language
DCP     Distributed Communications Processor
DCTS    Dimension Custom Telephone Service
DD      Daredevils
DD      Data Dictionary
DD      Days after Date
DD      Demand Draft
DD      Dishonorable Discharge
DD      Disk Drive
DD      Doctor of Divinity
D&D     Dungeons & Dragons
DDC     Digital Data Converter
DDCU    DC-to-DC Converter Unit [Space]
DDD     Direct Distance Dialing [Telephony] (principally US, elsewhere STD)
DDL     Document Description Language
DDN     Defense Data Network
DDP     Distributed Data Processing
DDS     Dataphone Digital Service [AT&T]
DDS     Digital Data Service
DDS     Direct Digital Service
DDS     Doctor of Dental Science
DDS     Doctor of Dental Surgery
DDT     DEC Debugging Tape
DDT     Di-<something> (pesticide)
DDT     Dynamic Debugging Technique
DE      Delaware
DEA     Drug Enforcement Agency [US Government]
DEAR    Department of Energy Acquisition Regulation
DEC     Digital Equipment Corporation [Corporate name]
DECUS   Digital Equipment Corporation Users Society
DES     Data Encryption Standard [NIST]
DEW     Distant Early Warning (as in DEW Line)
DF      Damage Free
D/F     Direction Finding
DFC     Distinguished Flying Cross
DFD     Data Flow Diagram
DFE     Data Flow Editor
DFM     Distinguished Flying Medal
DFN     Deutsche Forschungsnetz Verein (German Research Network Association)
DFRF    Dryden Flight Research Facility [Space]
DFS     Depth-First Search
DFW     Dallas-Ft.Worth (regional airport)
DG      Data General [Corporate name]
DG      Dei Gratia (by the grace of God)
DG      Director General
DGSC    Defense General Supply Center
DHHS    Department of Health and Human Services
DHSS    british Department of Health and Social Security
DHSS    Department of Health and Social Security (British)
DIA     Document Interchange Architecture
DIAD    (magnetic) Drum Information Assembler / Dispatcher
DIAL    Direct Information Access Line
DIAS    Defense Automatic Integrated System
DID     Direct Inward Dialing [Telephony]
DIF     Document Interchange Format
DIN     Deutsches Institut fur Normung
DIRE    Dire Is Really Emacs
DIS     Draft International Standard [ISO]
DISA    Data Interchange Standards Association
DISOSS  Distributed Office Support System [IBM]
DIY     Do It Yourself
DJ      Disc Jockey
DLA     Defense Logistics Agency
DLI     Data Link Interface(?)
DLL     Data Link Layer [ISO OSI]
DLL     Dial Long Line equipment
DLO     Dead Letter Office
DM      Dungeon Master
DMA     Direct Memory Access
DMD     Doctor of Dental Medicine
DME     Distance Measuring Equipment
DMF     Probably part of an X.400 address in Europe
DMOS    Diffusion Metal Oxide Semiconductor (see MOS)
DMSP    Defense Meteorological Satellite Program [Space]
DMV     Department of Motor Vehicles
DMV     Department of Motor Vehicles (Calif)
DMZ     DeMilitarized Zone
DNA     DeoxyriboNucleic Acid
DNA     Digital Network Architecture [DEC]
DNCRI   [NSF] (q.v.) Division of Networking and Communications Research and Infrastructure
DNHR    Dynamic NonHierarchical Routing
DNIC    Data Network Identification Code [Telephony]
DNIS    Dialed Number Identification Service (see also DID) [Telephony]
DNL     Director of Naval Laboratories
DNR     Dialed Number Recorder [Telephony]
DNS     Domain Name System
DOA     Dead On Arrival
DOB     Date Of Birth
DOC     Dynamic Overload Control
DOD     Department Of Defense [US Government] (sometimes DoD)
DOE     Department of Energy [US Government]
DOHC    Dual OverHead Cams [Automotive]
DOMAIN  Distributed Operating Multi Access Interactive Network (Apollo)
DOS     Disk Operating System
DOT     Department Of Transportation [US Government]
DOT&E   Director, Operational Test and Evaluation
DOV     Data Over Voice [Telephony]
DOY     Day of Year
DP      Data Processing
DP      Dial Pulse [Telephony]
DP      Displaced Persons (expelled from native land)
DP      Display Postscript
DP      Double Penetration
DP      Double Play
DP      Draft Proposal
DPA     Delegation of Procurement Authority
DPANS   Draft Proposed American National Standard
DPI     Dots Per Inch
DPS     Display PostScript
DQ      Dairy Queen
DQ      Dragon Quest
DQDB    Distributed Queue Dual Bus (IEEE 802.6) [Telephony, Networking]
DQL     Database Query Language
DR      Dead Reckoning
DR      Dining Room
DRAM    Dynamic Random Access Memory (as opposed to static RAM)
DRD     Data Reading Device
DRE     Directional Reservation Equipment
DRG     Democratic Republic of Germany (East Germany)
DRI     Defense Research Internet
DRI     Digital Research, Incorporated [Corporate name]
d.s.    died single [Genealogy]
DS      Double-Sided
DS      Draft Standard
DSA     Dial System Assistance
DSE     Data Structure Editor
DSEE    Domain Software Engineering Environment
DSM     Distinguished Service Medal
DSO     Distinguished Service Order
DSP     Decessit Sine Prole (died without issue)
DSP     Digital Signal Processing
DSRI    Digital Standard Relational Interface
DSS     Decision Support System
DSS     Direct Station Selection [Telephony]
DST     Daylight Saving Time
DSTN    Double SuperTwisted Nematic
DSU     Digital Service Unit
DT      Delirium Tremens
DTE     Data Terminal Equipment
DTF     Dial Tone First payphone [Telephony]
DTMF    Dial Tone Multi Frequency [Telephony]
DTP     DeskTop Publishing
DTR     Data Terminal Ready (EIA RS-232-C)
DUI     Driving Under the Influence
DUT     Device Under Test
DV      Deo Vo lente (God willing)
DVM     Digital Volt Meter
DVM     Doctor of Veterinary Medicine
DWAPS   Defense Warehousing Automated Processing System
DWI     Died Without Issue [Genealogy]
DWI     Driving While Intoxicated
DWIM    Do What I Mean
DX      Distance (as in long distance radio communication)
DXT     Data eXtractT facility
d.y.    died young [Genealogy]
E       East
E       Espionage
EADASS  Engineering and Administrative Data AcquiSition System
EAFB    Edwards Air Force Base [Space]
EAN     Certainly part of an X.400 Address in Europe
EARN    European Academic Research Network
EAS     Extended Area Service (or Engineering Admin. System)
EASI    European Academic Supercomputer Initiative (of IBM)
EBCDIC  Extended Binary Coded Decimal Interchange Code
EC      Exchange Carrier [Telephony]
ECAFE   Economic Commission for Africa and the Far East
ECASS   Electronically Controlled Automatic Switching System
ECASS   Export Control Automated Support System
ECC     Error Correction Code
ECC     Error Correction Code (corrects error in memory or transmission)
ECCM    Electronic Counter-CounterMeasures
ECDO    Electronic Community Dial Office
ECG     ElectroCardioGram
ECL     Emitter Coupled Logic (see also TTL)
ECLSS   Environmental Control and Life Support System [Space]
ECM     Electronic Counter Measure
ECM     European Common Market
ECMA    European Computer Manufacturers Association
ECO     Ecological
ECO     Electronic Central Office
ECO     Engineering Change Order
ECPA    Electronic Communications Privacy Act [US law]
ECS     Environmental Control System [Space]
ECT     ElectroConvulsive Therapy
ECV     Electric Cargo Vehicle [NASA OEXP]
ED&D    Expert Dungeons & Dragons
EDGAR   Electronic Data Gathering, Analysis, and Retrieval
EDI     Electronic Data Interchange
EDIF    Electronic Design Interchange Format
EDO     Extended Duration Orbiter [Space]
EDP     Electronic Data Processing
EDS     Electronic Data Systems
EDT     Eastern Daylight Time
EDTA    Ethylene Diamine Tetraacetic Acid
EDTCC   Electronic Data Transmission Communications Central
EE      Electrical Engineer
EE      Electrical or Electronics Engineer
EEC     European Economic Community
EEC     European Economic Comunity
EEG     ElectroEncephaloGram
EEL     Epsilon Extension Language
E&EO    Errors and Omissions Excepted
EEPROM  Electrically Erasable Programmable Read Only Memory
EFF     Electronic Frontier Foundation
e.g.    ??? (Latin(?): for example)
EGA     Enhanced Graphics Adapter
EGP     Exterior Gateway Protocol [Internet]
EGRET   Energetic Gamma Ray Experiment Telescope (on GRO) [Space]
EHF     Extremely High Frequency (30-300GHz)
EIA     Electronic Industries Association
EINE    EINE Is Not Emacs
EISA    Extended Industry-Standard Architecture
EISS    European Intelligence Support System
EKG     ElectroKardioGramm (see ECG)
EL      ElectroLuminescent (as in display)
ELF     Extremely Low Frequency
ELO     Electric Light Orchestra
ELP     Emerson, Lake and Palmer (or Powell)
ELV     Expendable Launch Vehicle [Space]
E&M     ``Ear and Mouth''; receive and transmit leads of a signalling system
EM      Enlisted Man (see EW)
EMA     Electronic Mail Association
EMACS   Editor MACroS
EMACS   Eight Megabytes And Constantly Swapping
E-MAIL  Electronic MAIL
EMF     ElectroMotive Force
EMF     ElectroMotive Force (voltage)
EMI     ElectroMagnetic Interference
EMP     Electromagnetic Pulse
EMPRESS EnvironMental Pulse Radiation Environment Simulator for Ships
EMR     ElectroMagetic Response
EMR     ElectroMagnetic Response
EMS     Electronic Message System
EMS     Extended Memory Specification
EMT     Emergency Medical Technician
EMU     ElectroMagnetic Unit
EMU     Extravehicular Mobility Unit [Space]
ENIAC   Electronic Numerical Integrator and Calculator
ENS     ENSign
EO      End Office [Telephony]
EO      Erasable Optical
EOF     End Of File
EOM     End Of Month
EOS     Earth Observing System [Space]
EOWG    Engineering and Operations Working Group (under FNC)
EP      Experience Points
EP      Extended Play
EPA     Environmental Protection Agency
EPOS    Engineering and Project-management Oriented Support system
EPRI    Electric Power Research Institute
EPROM   Erasable Programmable Read Only Memory
EPS     Encapsulated PostScript
EPT     Empire of the Petal Throne
EQ      Educational Quotient (see IQ)
ER      Emergency Room
ERA     Earned Run Average
ERA     Entity-Relationship-Attribute
ERA     Equal Rights Amendment
ERD     Entity-Relation Diagram
ERE     Entity Relationship Editor
ERT     Earth Resources Technology [Space]
ES      Expert System
ESA     European Space Agency
ESA     European Space Agency [Space]
ESAC    Electronic Systems Assistance Center
ESDI    Enhanced Standard Device Interface
ESE     East South East
ESF     Extended Superframe Format [Telephony]
ESM     Electronic Support Measures
ESnet   Energy Sciences network (DoE) [Networking]
ESO     European Southern Observatory
ESO     European Southern Observatory [Space]
ESP     Extra Sensory Perception
ESPS    Entropic Signal Processing System
ESS     Electronic Switching System [Telephony]
ESSEX   Experimental Solid State EXchange
EST     Eastern Standard Time
ET      Eastern Time
ET      Extra Terrestrial [Space]
ET      (Shuttle) External Tank [Space]
ETA     Estimated Time of Arrival
ET/ACC  External Tank/Aft Cargo Carrier (see also ET) [Space]
ETC     Et cetera, and so on...
ETD     Estimated Time of Departure
ETFD    Electronic Toll Fraud Device [Telephony]
ETH     Eidgn\:oessiche Technische Hochschule (Swiss Federal Institute of Technology)
ETLA    Extended Three Letter Acronym [Space]
ETO     Earth-to-Orbit [Space]
ETR     Eastern Test Range [Space]
ETS     Electronic Translator System
ETV     Education TeleVision
EUUG    European Unix User Group
EUV     Extreme UltraViolet
EUV     Extreme UltraViolet [Space]
EUVE    Extreme UltraViolet Explorer [Space]
EVA     ExtraVehicular Activity
EVA     ExtraVehicular Activity [Space]
EVX     Electronic Voice eXchange
EW      Electronic Warfare
EW      Enlisted Woman (see EM)
EWOS    European Workshop for Open Systems
FA      Football Association (British soccer--a word derived from Association)
FAA     Federal Aviation Agency [US Government]
FACD    Foreign Area Customer Dialing
FAO     Food and Agriculture Organization [US Government]
FAQ     Frequently Asked Questions [Space]
FAR     Federal Acquisition Regulations
FAS     Foreign Agricultural Service
FAS     Free Alongside Ship
FASST   Flexible Architecture Standard System Technology
FAST    Fast Auroral SnapshoT explorer [Space]
FAT     Foreign Area Translation
FAX     FAcsimile
FB      Freight Bill
FBI     Federal Bureau of Investigation [US Government]
FCC     Federal Communications Commission [US Government]
FCC     Federal Computer Conference
FCCSET  Federal Coordinating Committee for Science, Education and Technology (under OSTP) {Maybe Eng. for Edu.??}
FCO     Field Change Order
FCO     Frequency Controlled Oscillator
FCS     Frame Check Sequence
FDA     Food and Drug Administration [US Government]
FDDI    Fiber Digital Data Interface
FDDI    Fiber Distributed Data Interface
FDHD    Floppy Drive High Density
FDIC    Federal Deposit Insurance Corporation
FDIC    Federal Deposit Insurance Corporation [US Government]
FDM     Frequency Division Multiplexing
FDR     Franklin Delano Roosevelt [US President]
FE      Field Engineer (see also CE, SE)
FEA     Finite Element Analysis
FEDSIM  FEDeral Systems Integration and Management center
FEMA    Federal Emergency Management Agency
FEMF    Foreign EMF (q.v.) (a.k.a. Cross Battery) [Telephony]
FEPC    Fair Employment Practices Commission
FEPG    Federal Engineering Planning Group (of FNC under EOWG, originally of FRICC)
FERS    Federal Employees Retirement System
FET     Federal Excise Tax
FET     Field Effect Transistor
FFA     Future Farmers of America
FFT     Fast Fourier Transform
FFT     Fast Fourier Transform [Space]
FG-A    Feature Group A [Telephony] (Line Side termination for LD carriers)
FG-B    Feature Group B [Telephony] (Trunk Side termination for LD carriers (aka ENFIA B), 950 service)
FG-D    Feature Group D [Telephony] (Trunk Side termination for LD carriers, 1+ service)
FGS     Fine Guidance Sensors (on HST) [Space]
FHA     Federal Home Administration
FHA     Future Homemakers of America
FIB     Focused Ion Beam
FICA    Federal Insurance Contributions Act
FIDO    Fog Investigation Dispersal Operation
FIFO    First In First Out (as in registers and buffers)
FILO    First In Last Out (see also FIFO)
FIMS    Forms Interface Management System
FINE    FINE Is Not Emacs
FIO     Frequency In and Out
FIPS    Federal Information Processing Standard
FIR     Far InfraRed [Space]
FIR     Finite Impulse Response
FIRMR   Federal Information Resource Management Regulation
FIT     Federal Information Technologies, inc.
FITS    Flexible Image Transport System [Space]
FIX     Federal Inter-agency eXchange [Networking]
FL      Florida
FLACC   Full Level Algol Checkout Compiler
FLEA    Four Letter Extended Acronym
FLL     Fixed Loss Loop [Telephony]
FLOP    FLoating point OPeration
FLOPS   FLoating-point OPerations per Second
FLRA    Federal Labor Relations Authority
FM      Frequency Modulation
FMB     Federal Maritime Board
FMCS    Federal Mediation and Conciliation Service
FMR     Follow Me Roaming [Telephony]
FMS     Financial Management Service (Treasury Dept) [US Government]
FMS     Forms Management System
FNC     Federal Networking Council (formerly FRICC) [US Government] (under OSTP)
FO      Foreign Office
FO      Forward Observer
FOAC    Federal Office Automation Center
FOB     Free On Board
FOB     Full Of Bull (aperiodical of) [TMRC]
FOC     Faint Object Camera (on HST) [Space]
FOC     Free Of Charge
FOIA    Freedom Of Information Act
FOIMS   Field Office Information Management System
FOIRL   Fiber Optic Inter(?) Repeater(?) Link(?) [Ethernet]
FOOBAR  See FUBAR [Net jargon]
FOR     Free On Rail
FORCS   Faa's Operational Reporting Communication System
FORD    Fix Or Repair Daily [Humor]
FORD    Found On Road Dead [Humor]
FORTRAN FORmula TRANslator
FOS     Faint Object Spectrograph (on HST) [Space]
FOSE    Federal Office Systems Exposition
FOT     Fiber Optic Transceiver [Ethernet]
FOT     Free On Truck
FOV     Field Of View
FPA     Floating Point Accelerator
FPC     Fish Protein Concentrate
FPE     Floating Point Engine
FPHA    Federal Public Housing Authority
FPLA    Field Programmable Logic Array (see PLA)
FPM     Feet Per Minute
FPO     Field Post Office
FPO     Fleet Post Office
fps     Feet Per Second
FPU     Floating Point Unit
FQDN    Fully Qualified Domain Name [TCP/IP] (DNS)
FR      Frame Relay [Telephony, Networking]
FRACTAL FRACTional dimensionAL
FRED    Fred Resembles Emacs Deliberately
FRG     Federal Republic of Germany (West Germany)
FRICC   Federal Research Internet Coordinating Committee (now FNC, q.v.) [Networking, US Government]
FROG    Free Rocket Over Ground
FRPG    Fantasy Role Playing Game
FRS     Federal Reserve System
FS      Field Service
FS      File System
FS      Full Standard
FSF     Free Software Foundation
FSK     Frequency Shift Keying
FSLIC   Federal Savings and Loan Insurance Corporation
FSS     Federal Supply Service
FSW     Forward Swept Wings
Ft      Foot
FTAM    File Transfer And Management (ISO upscale FTP)
FTC     Federal Trade Commission
FTL     Faster Than Light
FTP     File Transfer Protocol (esp. of the TCP/IP suite)
FTS     Federal Telecommunications System [Telephony, US Government]
FTS     Flight Telerobotic Servicer [Space]
FUBAR   F***ed Up Beyond All Recognition/Repair
FUBAR   Fouled Up Beyond All Recognition/Repair
FUSE    Far Ultraviolet Spectroscopic Explorer [Space]
FW      Fringeworthy
FWD     Front Wheel Drive
FWHM    Full Width at Half Maximum [Space]
FX      Foriegn eXchange [Telephony]
FY      Fiscal Year
FYI     For Your Information
G       General audiences [Movie rating]
G       Gravity
GA      Gamblers Anonymous
GA      General Assembly
GA      General Average
GA      General of the Army
GA      Georgia
GAAP    Generally Accepted Accounting Principles
GAB     Group Audio Bridging [Telephony]
Gaia    Earth's self-sustaining Biosphere (Not an acronym, from some ancient language, I think)
GAN     Global Area Network
GAO     General Accounting Office [US Government]
GAR     Grand Army of the Republic
GARR    Gruppo Arminizzazione Rete por la Ricerca (Italian Research Network Harmonization Group)
GAS     Get-Away Special [Space]
GATT    General Agreement on Tariffs and Trade
GAW     Guaranteed Annual Wage
GAW     Guarenteed Annual Wage
GB      Gangbusters
GB      GigaByte
GB      Great Britain
GBIP    General Purpose Interface Bus
GBT     Green Bank Telescope [Space]
GC      Garbage Collection (LISP)
GC      Gas Chromatograph (or Chromatography)
GCA     Ground Controlled Approach
GCC     Gnu C Compiler
GCD     Ground Controlled Descent
GCL     Graphics Command Language
GCM     General Court Martial
GCR     Group-Coded Recording (magnetic tape, 6250 bpi)
GCT     Greenwich Civil Time
GCVS    General Catalog of Variable Stars [Space]
GDB     Gnu DeBugger
GDP     Gross Domestic Product
GDS     Great Dark Spot [Space]
GE      General Electric
GEM     Giotto Extended Mission [Space]
GEM     Graphics Environment Manager
GEO     Geosynchronous Earth Orbit [Space]
GHQ     General HeadQuarters
GHRS    Goddard High Resolution Spectrograph (on HST) [Space]
GHz     Giga HertZ (unit of frequency, 1,000,000,000 cycles per second)
GI      Galvanized Iron
GI      Gastro Intestinal (as in upper GI)
GI      General Issue
GI      Government Issue
GID     Group ID [UNIX]
GIF     Graphics Interchange Format
GIGO    Garbage In Garbage Out
GIN     Graphics INput
GISS    Goddard Institute for Space Studies
GKS     Graphical Kernel Standard
GKS     Graphics Kernel System
GM      Game Master
GM      General Manager
GM      General Motors [Corporate name, Automobile]
GM      Guided Missile
GMBH    Gesellschaft Mit Beschraenkter Haftung
GMC     Giant Molecular Cloud [Space]
GMD     Gesellschaft f\:ur Mathematik und Datenverarbeitung (German Institute for Mathematics and Data Processing)
GMRT    Giant Meter-wave Radio Telescope [Space]
GMT     Greenwich Mean Time (also called UT)
GNP     Gross National Product
GNU     GNU's Not Unix
GOES    Geostationary Orbiting Environmental Satellite [Space]
GOES    Geostationary Orbiting Environmental Satellites [Space]
GOSIP   Government Open Systems Interconnection Profile (calls for government procurement of ISO/CCITT products)
GOSIP   Government OSI Profile
GP      General Practitioner
GP      General Purpose (RR engines and origin of Jeep) [Railroading, Automobile]
GPC     General Purpose Computer [Space]
GPI     Graphics Programming Interface
GPIB    General Purpose Interface Bus
GPIB    General-Purpose Interface Bus
GPL     GNU General Public Licence
GPO     General Post Office
GPO     Government Printing Office
GPS     Global Positioning System
GPS     Global Positioning System [Space]
GQ      General Quarters
GRB     Gamma Ray Burst(er)
GREP    Global Regular Expression Print, g/re/p, (UNIX command)
GREP    Global Regular Expression Print [UNIX]
GRO     Gamma Ray Observatory [Space]
GRS     Gamma Ray Spectrometer (on Mars Observer) [Space]
GRS     Great Red Spot [Space]
GS      General Schedule
GS      Glide Slope
GSA     General Services Administration
GSA     General Services Adminstration [US Government]
GSA     Girl Scouts of America
GSBCA   General Services administration Board of Contract Appeals
GSC     Guide Star Catalog (for HST) [Space]
GSFC    Goddard Space Flight Center (Greenbelt, MD) [NASA, Space]
GSI     Gesellschaft f\:ur Schwerionenforschung (German Federal Research Institute for Heavy Ion Research)
GSM     Global System Mobile
GSM     Groupe Speciale Mobile (Committee Designing preceding)
GSTS    Ground-based Surveillance and Tracking System
GT      Gross Ton
GTE     General Telephone and Electric [Corporate name]
GTO     Geostationary Transfer Orbit [Space]
GTSI    Government Technology Services, inc.
GUI     Graphical User Interface
GW      Gamma World
GWEN    Ground Wave Emergency Network
GWM     Generic Window Manager [X]
H       Harn
H       Height
HACD    Home Area Customer Dialing
HAL     Heuristically programmed ALgorithmic computer (movie 2001)
HAM     Hold And Modify
HAO     High Altitude Observatory [Space]
Hb      HemogloBin
HBM     Her British Majesty; His British Majesty
HBO     Home Box Office
HC      Holy Communion
HC      House of Commons
HCFA    Health Care Financing Administration
HCFC    hydrochlorofluorocarbon [Chemical]
HCL     High Cost of Living
HD      Hard Disk
HD      Heavy Duty
HD      Henry Draper catalog entry [Space]
HDA     Head Disk Assembly (in winchester disk drives)
HDBV    Host Data Base View
HDL     High Density Lipoprotein
HDLC    High-level Data Link Control [Networking]
HDTV    High Definition Television
HE      His Eminence
HE      His Excellency
HEAO    High Energy Astronomical Observatory [Space]
HEDM    High Energy-Density Matter [Space]
HEMP    Help End Marijuana Prohibition
HEO     High Earth Orbit [Space]
HEPnet  High Energy Physics network [Networking]
HERO    Hazards of Electromagnetic Radiation to Ordnance
HF      High Fantasy
HF      High Frequency (3-30MHz)
HFE     Human Factors Engineering
HFS     Hierarchical File System
HGA     High Gain Antenna [Space]
HHS     (US Department of) Health and Human Services
HI      Hawaii
HIIPS   Hud Integrated Information Processing Services
HLC     Heavy Lift Capability [Space]
HLL     High-Level Language
HLV     Heavy Lift Vehicle [Space]
HMC     Halley Multicolor Camera (on Giotto) [Space]
HMOS    High performance Metal Oxide Semiconductor (see MOS)
HMS     His/Her Majesty's Ship
HMT     His/Her Majesty's Transport
HNPA    Home Numbering Plan Area [Telephony]
HOBIS   HOtel Billing Information System
HOL     High-Order System
HOTOL   HOrizontal Take-Off and Landing
HP      Hewlett Packard, Inc. [Corporate name]
HP      High Pressure
HP      Higher Power (sort of an AA "in" term, usually God)
HP      Hit Points
HP      HorsePower
HPGe    High Purity Germanium
HPL/T   High-Productivity Languages/Tools
HQ      HeadQuarters
HR      Hertzsprung-Russell (diagram) [Space]
HR      House of Representatives
HRH     Her Royal Highness
HRH     His Royal Highness
HRI     High Resolution Imager (on ROSAT) [Space]
HS      High School
HSB     Hue, Saturation, Brightness
HSP     High Speed Photometer (on HST) [Space]
HST     Hawaiian Standard Time
HST     Hubble Space Telescope [Space]
HT      High Tension (as in electric power transmission)
HTK     Hits To Kill
HUAC    House Unamerican Activities Committee
HUD     Heads Up Display
HUD     Housing and Urban Development [US Government]
HUPD    Harvard University Police Department
HUT     Hopkins Ultraviolet Telescope (ASTRO package) [Space]
HV      High Voltage
HVAC    Heating, Ventilation, and Air Conditioning
HW2000  Highway 2000
HWM     High-Water Mark
Hz      HertZ (unit of frequency, cycles per second)
IAB     Internet Activities Board [Networking]
IAEA    International Atomic Energy Agency
IANA    Internet Assigned Numbers Authority ([e-mail])
IATA    International Air Transport Association
IAU     International Astronomical Union [Space]
IAUC    IAU Circular [Space]
IBM     Ingrained Batch Mentality
IBM     International Business Machines, Inc. [Corporate name]
IBM     Itty Bitty Machines
IBT     Illinois Bell Telephone
IC      Integrated Circuit
IC      Interexchange Carrier [Telephony] (see also IEC, IXC)
ICB     Interstate Computer Bank
ICBM    InterContinental Ballistic Missile
ICE     In-Circuit Emulator
ICE     International Cometary Explorer [Space]
ICI     Imperial Chemical Industries
ICJ     International Court of Justice
ICL     International Computers Ltd.
ICMP    Internet Control Message Protocol
ICP     Integrated Channel Processor
ICP     Inventory Control Points
ICRC    International Cosmic Ray Conference
ID      Idaho
ID      IDentification
IDA     Intercommunication Data Areas
IDA     International Dark-sky Association [Space]
IDA     International Development Association
IDDD    International Direct Distance Dial [Telephony]
IDE     Interactive Development Environments, inc
IDF     Intermediate Distributing Frame [Telephony]
IDL     Interactive Data Language [Space]
IDV     Interlibrational Derived Vehicle [Space]
i.e.    ???? (Latin(?): in other words (?))
IE      Indo-European
IEC     Inter-Exchange Carrier [Telephony] (see also IC, IXC)
IEE     Institute of Electrical Engineers [UK]
IEEE    Institute of Electrical and Electronic Engineers
IETF    Internet Engineering Task Force
IF      Intermediate Frequency (as in IF stage)
IFB     Invitation For Bids
IFC     International Finance Corporation
IFC     International Freighting Corporation
IFF     Identification - Friend or Foe
IFF     Interchange File Format
IFLA    International Federation of Library Associations
IFR     Instrument Flight Rules [Aviation]
IGES    Initial Graphics Exchange Standard
IGM     InterGalactic Medium [Space]
IGY     International Geophysical Year
IGY     International Geophysical Year [Space]
IHP     Indicated HorsePower
IHS     Integrated Hospital Support
IIA     Information Industry Association
IIE     Institute of Industrial Engineers
IIHF    International Ice Hockey Federation
IIL     Integrated Injection Logic
ILO     International Labor Organization
ILS     Instrument Landing System
ILV     Industrial Launch Vehicle [Space]
IMF     International Monetary Fund
IMHO    In My Humble Opinion [Net jargon]
IMO     In My Opinion [Net jargon]
IMP     Interface Message Processor [ARPANET/MILNET] (replaced by PSN)
IMSL    International Mathematical Subroutine Library
IN      Indiana
INADS   INitialization and ADministration System [Telephony]
INRA    Iesus Nazerenus Rex Iudaeorum (Jesus of Nazareth, King of the Jews)
INRIA   Institut National de Recherche en Informatique et Automatique
INS     Immigration and Naturalization Service
In-situ In Place [Latin]
INSTITUTE       INSTITUTE's Name Shows That It's Totally Unrelated To EMACS
INTAP   INteroperability Technology Association for information Processing
INWATS  INward Wide Area Telephone Service [Telephony]
I/O     Input/Output
IO      Input/Output (sometimes I/O)
IOC     International Operating Center [Telephony, US]
IOD     Identified Outward Dialing
IOOF    International Order of Odd Fellows
IOTA    Infrared-Optical Telescope Array [Space]
IOTA    International Occultation Timing Association [Space]
IOU     I Owe you(U)
IP      Information Provider [Telephony]
IP      Innings Pitched
IP      Intermediate Point
IP      Internet Protocol
IPC     Inter-Process Communication
IPE     Integrated Programming Environment
IPMS    InterPersonal Message Services
IPS     Inertial Pointing System [Space]
IPS     Information Processing Standards
IPSE    Integrated Project-Support Environment
IQ      Intelligence Quotient (see EQ)
IR      Index Register
IR      Infra-Red
IRA     Individual Retirement Account
IRA     Irish Republican Army
IRAF    Image Reduction and Analysis Facility [Space]
IRAS    InfraRed Astronomical Satellite [Space]
IRBM    Intermediate Range Ballistic Missile
IRDS    Information Resource Dictionary Standard
IRDS    InfraRed Detection Set
IRE     Institute of Radio Engineers (old name for the now IEEE, which see)
IRM     Information Resources Management
IRMS    Information Resources Management Service
IRS     Internal Revenue Service
IRTF    Internet Research Task Force
IS      Information Systems
IS      International Standard [ISO] (Beyond the DIS Stage)
ISA     Industry-Standard Architecture
ISAM    Indexed Sequential Access Method
ISAS    Institute of Space and Astronautical Science (Japan) [Space]
ISBD    International Bibliographic Description
ISC     Information Services Center
ISC     International Switching Center
ISCH    Interstitial-Cell-Stimulating Hormone (same as LH)
ISDN    Integrated Services Digital Network [Telephony]
ISDT    Integrated Systems Development Tool
ISEE    International Sun Earth Explorer (usually ISEE-3)
ISF     Information Systems Factory
ISFUG   Integrated Software Federal User Group
ISI     Information Sciences Institute
ISM     InterStellar Medium [Space]
ISO     Infrared Space Observatory [Space]
ISO     International Organization for Standardization
ISO     International Standards Organization [Space]
ISODE   ISO Development Environment
ISOO    Information Security Oversight Office
ISPM    International Solar Polar Mission
ISPM    International Solar Polar Mission (now Ulysses) [Space]
ISR     Institute of Snow Research
ISRG    Independent Space Research Group
ISV     Independent Software Vendor
ISY     International Space Year [Space]
IT      Industrial Technology
IT      Information Technology
ITC     Inter-Task Communication
ITS     Incompatible Timesharing System
ITT     International Telephone and Telegraph
ITU     International Telecommunications Union
ITUSA   IT Users Standards Association
IUE     International Ultraviolet Explorer [Space]
IUS     Inertial Upper Stage
IUS     Inertial Upper Stage [Space]
IUV     Interlibrational Utility Vehicle [Space]
IXC     Inter-eXchange Carrier [Telephony] (see also IC, IEC)
IXI     International (pan-European) X.25 Infrastructure
JACM    Journal of the Association for Computing Machinery
JANET   Joint Academic Network (UK)
JBS     John Birch Society
JC      Jesus Christ
JC      Joint Compound (plumbing)
JC      Julius Caesar
JC      Junior College
JCA     Jewelry Crafts Association
JCAC    Joint Civil Affairs Committee
JCAE    Joint Committee on Atomic Energy
JCEE    Joint Council on Economic Education
JCET    Joint Council on Educational Television
JCS     Joint Chiefs of Staff
JD      Justice Department
JDS     John Dewey Society
JEM     Japanese Experiment Module (for SSF) [Space]
JES     John Ericsson Society
JET     Joint European Torus (fusion research)
JFK     John F. Kennedy
JFK     John F. Kennedy (international airport)
JFMIP   Joint Financial Management Improvement Program
JGR     Journal of Geophysical Research
JGR     Journal of Geophysical Research [Space]
JI      Justice, Inc.
JIC     Joint Intelligence Center
JIC     Just in Case
JILA    Joint Institute for Laboratory Astrophysics [Space]
JIM     Job Information Memorandum
JINTACCS        Joint INteroperability of TActical Command and Control Systems
JIS     Japan Industrial Standards
JISC    Japanese Industrial Standards Committee
JIT     Just In Time
JMS     John Milton Society
JNT     Joint Network Team (UK)
JO      Job Order
JO      Junior Officer
JOVE    Jonathan's Own Version of Emacs
JOVIAL  Jules Own Version of the International Algorithmic Language
JPL     Jet Propulsion Laboratory
JPL     Jet Propulsion Laboratory [Space]
JRC     Junior Red Cross
JSC     Johnson Space Center
JSC     Johnson Space Center (NASA) [Space]
JSD     Jackson System Development
JSRC    Joint Services Review Committee
JTIDS   Joint Tactical Information Distribution Systems
JV      Junior Varsity
JvNC    John von Neumann (Super Computer) Center
JvNCnet John von Neumann (Super Computer) Center network
K       Kilo- (metric 1000)
K9      canine (K9 corps - army dogs)
KAIST   Korean Advanced Institute of Science and Technology
KAO     Kuiper Airborne Observatory [Space]
KB      KiloByte
KC      King's Counsel (QC when queen reigning)
KC      Knights of Columbus
KD      Kiln Dried
KD      Knocked Down
KDCI    Key Display Call Indicator
KERMIT  Kl-10 Error-free Reciprocal Micro Interconnect over Tty lines
KET     Kentucky Educational Television
KHz     Kilo HertZ (unit of frequency, 1000 cycles per second)
KI      Kiwanis International
KIA     Killed In Action
KIAS    Knot Indicated Air Speed
Km      Kilometers
KO      Knock Out [Boxing, Electric]
KP      Key Pulse [Telephony]
KP      Kitchen Police
KPNO    Kitt Peak National Observatory
KPO     KeyPunch Operator
KQC     King's College London
K&R     Kernighan and Ritchie, the c programming language
KS      King's Scholar
KSC     Kennedy Space Center (NASA) [Space]
KSU     Key System Unit [Telephony]
KTB     Cretaceous-Tertiary Boundary (from German) [Space]
KTS     Key Telephone System [Telephony]
KTU     Key Telephone Unit [Telephony]
KWIC    Key Word In Context
KY      Kentucky
L1      Lagrange Point #1 35,000 Miles above moon [Space]
L2      Lagrange Point #2 40,000 Miles behind moon [Space]
L3      Lagrange Point #3 (?? 35,000 Miles below moon) [Space]
L4      Lagrange Point #4 240,000 mile Earth orbit [Space]
L5      Lagrange Point #5 240,000 mile Earth orbit [Space]
LA      Los Angeles
LA      Louisiana
LA      Low Altitude
LADAR   LAser Detection And Ranging
LAM     Master of Liberal Arts
LAMA    Local Automatic Message Accounting [Telephony]
LAN     Local Apparent Noon
LAN     Local Area Network
LANL    Los Alamos National Laboratory [Space]
LANL    Los Alamos (NM) National Laboratory
LAPB    Link Access Procedure (Balanced)
LAPD    Link Access Procedure (??)
LAPD    Los Angeles (CA, US) Police Department
LAR     Local Acquisition Radar
LaRC    Langley Research Center (NASA) [Space]
LASER   Light Amplification by Stimulated Emission of Radiation
LAT     Local Apparent Time
LATA    Local Access and Transport Area [Telephony]
LAX     Los Angeles International Airport
LB      Light Bomber
LB      pound (LiBra)
LBHS    Long Beach High School
LBL     Lawrence Berkeley (Calif.) Labs
LBS     Pounds
LC      inductor-Capacitor circuit (as in filters, L is symbol inductance)
LCD     Liquid Crystal Display
LCD     Lowest Common Denominator
LCDR    Lieutenant Commander
LCL     Less than Carload Lot [Railroading]
LCL     Lunar Cargo Lander [NASA OEXP]
LCM     Least Common Multiple
LCM     Life Cycle Management
LCS     Laboratory for Computer Science (of MIT)
LCT     Landing Craft Tanks
LD      Long Distance [Telephony]
LDC     Long Distance Carrier [Telephony]
LDEF    Long Duration Exposure Facility [Space, NASA]
LDF     Large Deployable Reflector [Space]
LDL     Low Density Lipoprotein
LDX     Long Distance eXtender [Telephony]
LEAP    Low-power Enhanced At Portable
LEC     Local Exchange Carrier [Telephony]
LED     Light Emitting Diode
LEM     Lunar Excursion Module (a.k.a. LM) (Apollo spacecraft) [Space]
LEO     Low Earth Orbit [Space]
LEP     Large Electron-Positron collider [CERN]
LeRC    Lewis Research Center (NASA) [Space]
LEST    Large Earth-based Solar Telescope [Space]
LF      Low Frequency (30-300KHz)
LFSA    List of Frequently Seen Acronyms (!) [Space]
LGA     Low Gain Antenna [Space]
LGM     Little Green Men [Space]
LH      Left Hand
LH      Liquid Hydrogen (also LH2 or LHX) [Space]
LH      Lower Half
LH      Luteinizing Hormone (same as ISCH)
LHC     Large Hadron Collider [CERN]
LHD     Litterarum Humaniorum Doctor (doctor of human letters)
LHS     Left Hand Side
LI      Long Island
LIFIA   Laboratoire d'Informatique Fondamentale et d'Intelligence Artificielle
LIFO    Last In First Out (see FIFO)
LINC    Laboratory INstrument Computer
LISA    Large Installation Systems Administration (USENIX specific?)
LISP    LISt Processing Language
LIU     Line Interface Unit
LL      Late Latin
LL      Long Lines [Telephony]
LLB     Legum Baccalaureus (bachelor of laws)
LLD     Legum doctor (doctor of laws)
LLN     Line Link Network [Telephony]
LLNL    Lawrence Livermore National Laboratories
LLO     Low Lunar Orbit [Space]
LLOX    Lunar Liquid Oxygen [Space]
LLP     Line Link Pulsing [Telephony]
LM      Life Master (Contract Bridge ranking)
LM      Lunar Module (a.k.a. LEM) (Apollo spacecraft) [Space]
LMC     Large Magellanic Cloud (see SMC)
LMC     Large Magellanic Cloud [Space]
LMOS    Line Maintenance Operations System [Telephony, AT&T]
LN2     Liquid N2 (Nitrogen) [Space]
LNG     Liquified Natural Gas
LOA     Lands of Adventure
LOFT    Launch Operations Flight Test [Space]
LOOPS   Lisp Object Oriented Programming System
LOP     Lines Of Position
LOSF    Lunar Orbit Staging Facility [Space]
LOTS    Low Overhead Timesharing System
LOX     Liquid Oxygen
LOX     Liquid OXygen [Space]
LP      Long Play(ing) (record)
LP      Low Pressure
LPC     Linear Predictive Coding (speech processing)
LPDA    Link Problem Determination Aid
LPF     League for Programming Freedom
LPG     Liquefied Petroleum Gas
LPG     Low Pressure Gas
LPL     Lunar Personnel Lander [NASA OEXP]
LPN     Licensed Practical Nurse
LPP     Licensed Program Products
LPR     Line PrinteR
LPT     Lunar Propellant Tanker [NASA OEXP]
LPV     Lunar Piloted Vehicle [NASA OEXP]
LRB     Liquid Rocket Booster [Space]
LRBM    Long Range Ballistic Missile
LRC     Longitudinal Redundancy Character
LRU     Least Recently Used
LRU     Line Replaceable Unit
LRV     Light Rail Vehicle [Railroading]
LS      Left Side
LS      Letter Signed
LS      Locus Sigilli (place of seal)
LSAP    Logical(?, maybe Link) Service Access Point [OSI, Networking]
LSB     Least Significant Bit; Least Significant Byte
LSB     Lower Side Band
LSC     Lecture Series Committee (of MIT)
LSC     LightSpeed C
LSD     Least Significant Digit
LSD     LySergic acid Diethylamide
LSD     pounds (Libra), shillings (Sestertii), and (old) pence (Denarii)
LSI     Large Scale Integration
LSP     LightSpeed Pascal
LSR     Local Standard of Rest [Space]
LSS     Life Support System
LSS     Loop Switching System
LSSD    Level-Sensitive Scan Detection
LT      Long Ton
LT      Low Tension
LTC     Lieutenant Colonel
LTJG    Lieutenant Junior Grade
LTL     Less than Truckload Lot
LTP     Lunar Transient Phenomenon [Space]
LUG     Local Users Group
LUT     Look-Up Table
LWM     Low-Water Mark
LWT     London Weekend Television [Corporate name]
LZ      Landing Zone
M       Mega- (metric 10^6)
m       meter(s)
m       milli- (metric 1/1000)
M       Miniatures
MA      Massachusetts [US state postal designation]
MAAP    Maintenance And Administration Panel
MAC     an MIT interdepartmental lab (stands for many things) (renamed to LCS)
MAC     Media Access Control
MAC     Medium Access Control
MAC     Military Air Command
MACSYMA project MAC's SYmbolic MAnipulation System
MAD     Mutual Assured Destruction
MADD    Mothers Against Drunk Driving
MAG     Magazine
MAN     Metropolitan Area Network
MAP     Manufacturing Automation Protocol
MAP/TOP Manufacturing Automation Protocol/Technical Office Protocol
MARBI   MAchine Readable form of Bibliographic Information
MARC    MAchine Readable card Catalog
MARS    Multiuser Archival and Retrieval System
MASC    Multiple Award Schedule Contract
MASER   Microwave Amplification by Stimulated Emission of Radiation
MASH    Mobile Army Surgical Hospital
MAST    Multi-Application SOnar Trainer
MAT-CALS        Marine Air Traffic-Control And Landing System
MAU     Math Acceleration Unit
MAU     Media Access Unit
MAU     Medium Access Unit
MB      Manned Base [Space]
MB      MegaByte
MBA     Master Business Administration
MBTA    Massachusetts Bay Transportation Authority
MC      Master of Ceremonies
MCA     Micro Channel Architecture
MCAE    Mechanical Computer Aided Engineering
MCC     Master Control Console
MCC     Microelectronics and Computer technology Corporation
MCC     Mission Control Center [Space]
MCP     Master Control Program
MCP/AS  Master Control Program/Advanced System
MCPO    Master Chief Petty Officer
MCSV    Mars Crew Sortie Vehicle [NASA OEXP]
MD      Doctor of Medicine
MD      Maryland
MD      Maryland [US state postal designation]
MD      Medical Doctor
MD      Months after Date
MDAS    Magnetic Drum Auxiliary Sender
MDC     Metropolitan District Commision (Mass State Agency)
MDE     Modular Design Environment
MDF     Main Distribution Frame [Telephony]
MDRE    Mass Driver Reaction Engine [Space]
MDT     Mean Down Time
ME      Maine
ME      Mechanical Engineer
MECO    Main Engine CutOff [Space, Shuttle]
MEd     Master of EDucation
MERP    Middle-Earth Role Playing
MeV     Million Electron Volts
MF      Medium Frequency (300-3000KHz)
MF      Middle French
MF      Multi-Frequency [Telephony]
MFA     Master Fine Arts
MFA     Museum of Fine Arts [Boston]
MFJ     Modified Final Judgment [Telephony]
MFLOPS  Million FLoating-point OPerations per Second (see also FLOPS)
MFM     Modified Frequency Modulation
MFS     Macintosh File System
MG      Machine Gun
MG      Major General
MG      Military Government
MGH     Massachusetts General Hospital
MGM     Metro-Goldwyn Mayer [Corporate name]
MHD     MagnetoHydroDynamics
MHS     Mail Handling System [ISO]
MHz     Mega HertZ (unit of frequency, 1,000,000 cycles per second)
MI      Michigan
MI      Military Intelligence
MIA     Missing In Action
MIB     Management Information Base
MIDI    Musical Instrument Digital Interface
MIFASS  Marine Integrated Fire And Support System
MILNET  MILitary NETwork
MIM     Morality In Media
MIMD    Multiple Instruction, Multiple Data
MINCE   MINCE Is Not Complete Emacs
MINE    MINE Is Not Emacs (but it is mine)
MIPS    Million Instructions Per Second
Mir     Peace [Russian]
MIRV    Multiple Independently-Targetable Reentry Vehicle
MIS     Management Information System
MIT     Massachusetts Institute of Technology
ML      Middle Latin
mL      milliliter(s)
MLA     Member of Legislative Assembly (see MPP)
MLD     Minimum Lethal Dose
MLL     Mars Logistics Lander [NASA OEXP]
MLS     Microwave Landing System
MLS     Multi-Level Security
MLV     Medium Lift Vehicle [NASA OEXP]
MM      Maryknoll Missioners
mm      millimeters
MMES    Martin Marietta Energy Systems
MMFS    Manufacturing Message Format Standard
MMH     MonoMethyl Hydrazine [Space]
MMM     see 3M
MMT     Multiple Mirror Telescope [Space]
MMU     Manned Maneuvering Unit [Space]
MMU     Memory Management Unit
MMW     Multi-Mega Watt [Space]
MN      Minnesota
MNA     Member of National Assembly (Quebec)
MNP     Microcom Networking Protocol [Corporate name]
MNRAS   Monthly Notices of the Royal Astronomical Society [Space]
MO      Mail Order
MO      Medical Officer
MO      Missouri
MO      Modus Operandi
MO      Money Order
MOC     Mars Observer Camera (on Mars Observer) [Space]
MOD     Ministry of Defence (UK) (sometimes written MoD)
MOL     Manned Orbiting Laboratory [Space]
MOLA    Mars Observer Laser Altimeter (on Mars Observer) [Space]
MOMA    Museum of Modern Art [New York]
MOMV    Manned Orbital Maneuvering Vehicle [Space]
MOR     Middle-Of-the-Road
MOS     Metal Oxide Semiconductor
MOSFET  Metal Oxide Semiconductor Field Effect Transistor
MOTAS   Member Of The Appropriate Sex
MOTIS   Member Of The Inappropriate Sex
MOTIS   Message-Oriented Text Interchange System
MOTOS   Member of the Opposite Sex
MOTSS   Member of the Same Sex
MOTV    Manned Orbital Transfer Vehicle [Space]
MOU     Memorandum Of Understanding
MOUSE   Minimum Orbital Unmanned Satellite of Earth
MP      Melting Point
MP      Member of Parliament
MP      Metropolitan Police
MP      Military Police(man)
MPC     Minor Planets Circular [Space]
MPE     Mission to Planet Earth [Space]
MPG     Miles Per Gallon
MPH     Miles Per Hour
MPP     Member of Provincial Parliament (Canada; also MLA)
MPR     Mars Pressurized Rover [Space]
MPV     Mars Piloted Vehicle [NASA OEXP]
MPW     Macintosh Programmer's Workshop
MR      Miniatures Rules
MRI     Magnetic Resonance Imaging
MRP     Manufacturing Requirements Planning
MRSR    Mars Rover and Sample Return [Space]
MRSRM   Mars Rover and Sample Return Mission [Space]
MS      ManuScript
MS      Master of Science
MS      Military Science
MS      Motor Ship
MS      Multiple Sclerosis
MSB     Most Significant Bit; Most Significant Byte
MSC     MicroSoft C
MSCP    Mass Storage Control Protocol
MSD     Most Significant Digit
MS-DOS  MicroSoft DOS
MSE     Mobile Subscriber Equipment
MSFC    (George C.) Marshall Space Flight Center (NASA) [Space]
MSFC    Marshall Space Flight Center
MSG     MonoSodium Glutamate
MSH     Marvel Super Heroes
MSL     Mean Sea Level
MSPCA   Massachussetts Society for the Prevention of Cruelty to Animals
MSPE    Mercenaries, Spies & Private Eyes
MSRP    Manufacturer's Suggested Retail Price
MSS     Management Support System
MSS     ManuScriptS
MSS     Mass Storage System
MSS     Maximum Segment Size [TCP/IP] (see also MTU)
MST     Mountain Standard Time
MT      Metric Ton
MT      Mountain Time
MTA     Message Transfer Agent
MTA     Metropolitan Transportation Authority
MTBF    Mean Time Between Failures
MTC     Man Tended Capability [Space]
MTR     Magnetic Tape Recording
MTSO    Mobile Telephone Switching Office [Telephony]
MTTF    Mean Time To Failure
MTTR    Mean Time To Recovery
MTTR    Mean Time To Repair
MTU     Maximum Transfer Unit [Networking] (see also MSS)
MTV     Music TeleVision
MUF     Maximum Usable Frequency (max freq during sunspot activity)
MULTICS MULTiplex Information Computer Services
MUMPS   Mgh Utility MultiProgram System
MUNG    Mung Until No Good (see the hacker's dictionary)
MUX     MUltipleXor
MVA     MegaVolt Ampere
MVS     Multiple Virtual Storage [IBM]
MX      Missile eXperimental
N       North
N       Notice
NA      Narcotics Anonymous
NA      North America
NA      Not Applicable
NAACP   National Association for the Advancement of Colored People
NAAS    North American Automated Systems co.
NAB     National Association of Broadcasters
NABISCO NAtional BIScuit COmpany [Corporate name]
NACCIRN North American Coordinating Committee for Intercontinental Research Networking (see also CCIRN)
NACS    National Advisory Committee on Semiconductors
NAD     Network Access Device
NADGE   NATO Air Defense Ground Environment
NAG     Numerical Algorithms Group
NAGE    National Association of Government Employees
NAK     Negative AcKnowledge
NAM     Name and Address Module [Telephony] (cellular phone changeable ROM)
NAM     National Account Manager [Telephony, AT&T]
NAM     Number Assignment Module [Telephony] (cellular phone changeable ROM)
NANP    North American Numbering Plan
NAPAP   National Acid Precipitation Assessment Program
NAR     Nuclear Acoustic Resonance
NARDAC  NAvy Regional Data Automation Center
NAS     National Academy of Sciences
NAS     National Advanced Systems
NASA    National (US) Aeronautics and Space Administration [Space]
NASDA   NAtional (Japan) Space Development Agency [Space]
NASM    National (US) Air and Space Museum [Space]
NASP    National (US) AeroSpace Plane [Space]
NATO    North Atlantic Treaty Organization
NAVDAC  NAVal Data Automation Command
NAVSWC  NAVal Surface Weapons Center
NB      New Brunswick
NB      Nota Bene
NBA     National (US) Basketball Association
NBC     National (US) Broadcasting Company [Corporate name]
NBFM    NarrowBand Frequency Modulation
NBO     Network Build Out
NBS     National Bureau of Standards (renamed NIST) [US Government]
NBVM    Narrow Band Voice Modulation
NC      No Charge
NC      No Connection
NC      North Carolina
NCA     Network Control Analysis
NCC     National (US) Computer Conference
NCC     National (US) Council of Churches
NCDC    National (US) Climatic Data Center
NCE     New Catholic Edition
NCGA    National (US) Computer Graphics Association
NCI     National (US) Cancer Institute [US Government]
NCIC    National (US) Cartographic Information Center
NCO     Non-Commissioned Officer
NCP     Network Control Program
NCR     National (US?) Cash Register [Corporate name]
NCS     Network Computing System
NCSA    National (US) Center for Supercomputing Applications
NCSC    National (US) Computer Security Center [NSA]
NCTL    National Computer and Telecommunications Laboratory
NCV     No Commercial Value
ND      No Date
ND      North Dakota
NDA     Non-Disclosure Agreement
NDDL    Neutral Data Definition Language
NDE     News Development Environment
NDEA    National (US) Defense Education Act
NDL     Network Database Language
NDP     New Democratic Party (Canada)
NDSL    National (US) Defense Student Loan
NDSL    National (US) Direct Student Loan
NDT     Newfoundland Daylight Time
NDV     NASP Derived Vehicle
NDV     NASP Derived Vehicle [Space]
NE      New England
NE      North East
NEAR    National Electronic Accounting and Reporting system
NEARnet New England Academic and Research Network
NEB     New English Bible
NEC     Nippon Electric Company [Corporate name]
NEI     Not Elsewhere Included
NES     National Energy Strategy
NES     Not Elsewhere Specified
NESC    National Energy Software Center
NET     National (US) Educational Television
NET     NETwork
NET     New England Telephone
NEWS    Network extensible Window System
NEXRAD  NEXt generation weather RADar
NF      No Funds
NFC     National (US) Football Conference
NFFE    National (US) Federation of Federal Employees
NFL     National (US) Football League
NFS     Network File System
NG      National Guard
NG      No Good
NGC     New General Catalog [Space]
NH      New Hampshire
NHI     National Health Insurance
NHL     National (Canada) Hockey League
NHLBI   National Heart, Lung, and Blood Institute (Bethesda, MD)
NIC     Network Information Center ("The NIC" is NIC.DDN.MIL)
NICMOS  Near Infrared Camera / Multi Object Spectrometer (HST upgrade) [Space]
NIFTP   (a file transfer network in the UK)
NIH     National (US) Institutes of Health
NIH     Not Invented Here
NIM     Nuclear Instrumentation Module (an electronic instr. standard)
NIMH    National Institute of Mental Health (Rockville, MD)
NIMS    Near-Infrared Mapping Spectrometer (on Galileo) [Space]
NIR     Near InfraRed [Space]
NIS     Network Information System (formerly yp)
NISO    National Information Standards Organization
NIST    National Institute of Standards and Technology (formerly NBS) [US Government]
NJ      New Jersey
NJB     New Jersey Bell [Telephony]
NL      National League (baseball)
NLM     National Library of Medicine
NLP     Natural Language Processing
NLRB    National Labor Relations Board
NLS     Network License Server
NM      Nautical Mile
NM      New Mexico
NM      Night Message
NM      No Mark; Not Marked
NMOS    N channel Metal Oxide Semiconductor (N-MOS) (see MOS)
NMR     Nuclear Magnetic Resonance
NMS     Network Monitoring Station
NNE     North North East
NNTP    Net News Transfer Protocol
NNW     North North West
NNX     NANP syntax for a three-digit string, N:{2-9}, X:{0-9} [Telephony]
NOA     NSWC Office Automation
NOAA    National Oceanic and Atmospheric Administration [Space, US Government]
NOAO    National (Tucson, AZ, US) Optical Astronomical Observatories [Space]
NOC     Network Operations Center
NORAD   NORth American Defense Command
NORM    Naturally Occuring Radioactive Material
NORML   National Organization for the Reform of Marijuana Laws
NOS     Not Otherwise Specified
NOSC    Naval Ocean Systems Center
NOTIS   Network Operator Trouble Information System
NOW     Negotiable Order for Withdrawal [Banking] (Is this MA or NE specific?)
NOx     Nitrogen Oxides
NP      No Protest
NP      Nondeterministic-Polynomial
NP      Notary Public
NP      Noun Phrase
NPA     Numbering Plan Area (area code) [Telephony]
NPC     Non-Player Character (see PC) [Role-playing]
NPL     National Physical Laboratory (UK)
NPL     Non-Procedural Language
NPN     Negative-Positive-Negative (transistor)
NPN     NonProtein Nitrogen
NPR     National Public Radio
NPR     non-Processor Request [PDP11, UNIBUS]
NQS     Network Queuing System
NRA     National Reconstruction Act (FDR era US)
NRA     National Rifle Association
NRAO    National Radio Astronomical Observatory [Space]
NRC     National Research Council
NRC     Nuclear Regulatory Commission
NRE     Non-Recurring Engineering (as in NRE costs)
NREN    National (US) Research and Education Network
NRL     Naval Research Labs
NRO     National Reconnaissance Office
NRO     National Reconnaissance Organization [Space]
NRZ     Non-Return to Zero
NRZI    Non-Return to Zero Inverted (magnetic tape, 800 bpi)
NS      Neutron Star [Space]
NS      Not Specified
NS      Nova Scotia
NS      Nuclear Ship
NSA     National Security Agency [US Government]
NSAP    Network Service Access Point [OSI, Networking]
NSC     National (US) Security Council [US Government]
NSE     Network Software Environment
NSF     National (US) Science Foundation [US Government]
NSS     Nodal Switching System [NSFnet]
NSSDC   National Space Science Data Center [Space]
NST     Newfoundland Standard Time
NSTS    National Space Transportation System [Space]
NSW     New South Wales (Australia)
NSWC    Naval Surface Warfare Center
NSWC    Naval Surface Weapons Center
NT      New Testament
NT      Newfoundland Time
NT      Northern Territory
NTEU    National Treasury Employees Union
NTIS    National Technical Information Service
NTN     Neutralized Twisted Nematic
NTP     Network Time Protocol [Internet]
NTP     Normal Temperature and Pressure (see STP)
NTSB    National Transportation Safety Board [US Government]
NTSC    National Television Standards Committee
NTSC    Never Twice Same Color
NTT     New Technology Telescope [Space]
NTT     Nippon Telephone & Telegraph
NU      Name Unknown
NURBS   NonUniform Rational B-Spline
NUSC    Naval Underwater Systems Center [US Government]
NV      Nevada
NW      North West
NWNET   NorthWestNet
NWS     National Weather Service
NWT     North West Territories (Australia)
NXX     NANP syntax for a three-digit string, N:{2-9}, X:{0-9} [Telephony]
NY      New York
NYC     New York City
NYNEX   New York and New England (Telephone)
NYPD    New York Police Department
NYSE    New York Stock Exchange
NYSERNet        New York State Educational and Research Network
NZ      New Zealand
NZUSUGI New Zealand Unix System User Group, Inc.
OA      Office Automation
OA      Overeaters Anonymous
OAO     Orbiting Astronomical Observatory [Space]
OAS     Organization of American States
OATS    Office Automation Technology and Services
OBE     Order of the British Empire
OBS     Omni Bearing Selector
OC      Order of Canada
OCDM    Office of Civil Defense and Mobilization
OCI     Out of City Indicator
OCLC    Online Computer Library Center, Inc.
OCLC    Online Computer Library Center (Ohio College Library Catalog)
OCO     Object Code Only
OCR     Optical Character Recognition
OCS     Officer Candidate School
OCST    Office of Commercial Space Transportation [Space]
OD      Doctor of Optometry
OD      Oculus Dexter (right eye)
OD      Officer of the Day
OD      OverDose
ODI     Optical Digital Image
ODISS   Optical Digital Image Storage System
ODT     Octal Debugging Technique
ODT     Online Debugging Technique
OE      Old English
OED     Oxford English Dictionary
OEM     Original Equipment Manufacturer
OEO     Office of Economic Opportunity
OES     Order of the Eastern Star
OEXP    Office of Exploration [NASA]
OF      Old French
OFM     Order of Friars Minor
OFS     Order of Free State
OG      Original Gum
OH      Ohio
OIRA    Office of Information and Regulatory Affairs
OIU     Office Interface Unit
OJT     On the Job Training
OLTP    On-Line Transaction Processing
OMB     Office of Management and Budget [US Government]
OMD     Orchestral Manouevers in the Dark
OMS     Orbital Maneuvering System [Space]
OMV     Orbital Maneuvering Vehicle [Space]
ON      Old Norse
ONC     Open Network Computing
ONI     Office of Naval Intelligence
ONI     Operator Number Identification [Telephony]
ONR     Office of Naval Research
OOP     Object Oriented Programming
OOPART  Out Of Place ARTifact
OOPS    Object-Oriented Programming System
OP      Observation Post
OP      OFFICEPOWER office automation system, trademark of CCI
OP      Order of Preachers
OP      Out of Print
OPEC    Organization of Petroleum Exporting Countries
OPF     Orbiter Processing Facility [Space]
OPM     Office of Personnel Management
OPUS    Obvious Password Utility System (Eugene Spafford <[e-mail]>)
OR      Operating Room
OR      Oregon
OR      Owner's Risk, Own Risk
ORFEUS  Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer [Space]
ORNL    Oak Ridge National Laboratory
OROM    Optical Read Only Memory
OS      Oculus Sinister (left eye)
OS      Operating System
OS      Ordinary Seaman
OS      Out of Stock
OSB     Order of St. Benedict
OSC     Orbital Sciences Corporation [Space]
OSCAR   Orbiting Satelite Carry Amateur Radio (1st launched 12 Dec 1961)
OSCAR   Orbiting Satellite Carry Amateur Radio (1st launched 12 Dec 1961)
OSCAR   Orbiting Satellite Carrying Amateur Radio [Space]
OSCRL   Operating System Command Response Language
OSD     Office of the Secretary of Defense
OSDIT   Office of Software Development and Information Technology
OSF     Open Software Foundation
OSF     Open Systems Foundation
OSF     Order of St. Francis
OSHA    Occupational Safety and Health Administration [US Government]
OSI     Office of Scientific Integrity [NIH]
OSI     Open Systems Interconnection (per ISO; 7 layer model)
OSI/RM  Open Systems Interconnection/Reference Model
OSME    Open Systems Message Exchange
OSP     Optical Storage Processor
OSPFIGP Open Shortest-Path First Internal Gateway Protocol [Internet]
OSS     Office of Strategic Services (later CIA)
OSS     Office Support System
OSS     Operation Support System [Telephony, AT&T]
OSSA    Office of Space Science and Applications [Space]
OSSE    Oriented Scintillation Spectrometer Experiment (on GRO) [Space]
OSTP    Office of Science and Technology Policy
OSTP    (White House) Office of Science and Technology Policy [US Government]
OT      Old Testament
OT      OverTime
OTA     Office of Technical Assistance
OTA     Office of Technology Assessment
OTA     Optical Telescope Assembly (on HST) [Space]
OTB     Off-Track Betting
OTC     Over The Counter (stocks)
OTF     Open Token Foundation
OTH-B   Over The Horizon - Backscatter (as in radar)
OT&LF   Open Taxi & Limousine Foundation
OTR     On The Rag
OTS     Officers' Training School
OTV     Orbital Transfer Vehicle [Space]
OUTWATS OUTward Wide Area Telephone Service [Telephony]
OV      Orbital Vehicle [Space]
OV      Orbiter Vehicle [Space]
PA      Pennsylvania
PA      Per Annum
PA      Play Aid
PA      Power of Attorney
PA      Press Agent
PA      Private Account
PA      Public Address
PA      Purchasing Agent
PABX    Private Automatic Branch eXchange [Telephony]
PACCOM  Pacific Computer Communications network consortium [Networking]
PACX    Private Automatic Computer eXchange
PAD     Packet Assembler-Disassembler [Networking]
PAH     Polycyclic Aromatic Hydrocarbon
PAL     Phase Alternation Line-rate
PAL     Programmable Array Logic
PAM     Payload Assist Module [Space]
PAM     Pulse Amplification Modulation
PARC    Palo Alto Research Center, xerox
PASS    Personal Access Satellite System [NASA]
PATROL  Program for Administrative Traffic Reports On Line
PBM     Play By Mail game
PBS     Public Broadcasting System
PBX     Private Branch eXchange [Telephony]
PC      Peace Corps
PC      PerCent; PerCentage
PC      Personal Computer (IBM wants you to believe a specific kind)
PC      Player Character (see NPC) [Role-playing]
PC      Post Card
PC      Post Cibum (after meals)
PC      Privileged Character
PC      Privy Council
PC      Program Counter
PC      Progressive Conservative party [Canada]
PC      Providence College
PC/AT   Personal Computer/Advanced Technology
PCB     PolyChlorinated Biphenyl
PCB     Printed Circuit Board
PC-DOS  Personal Computer DOS
PCI     Panel Call Indicator
PCIE    President's Council on Integrity and Efficiency
PCL     Printer Command Language
PCM     Plug-Compatible Mainframe
PCM     Pulse Code Modulation
PCPC    Personal Computers Peripheral Corporation
PCS     Permanent Change of Station
PCTE    Portable Common Tools Environment
PCTS    Posix Conformance Test Suite
PD      Per Diem
PD      Police Department
PD      Potential Difference
PD      Public Domain
PDAD    Proposed Draft ADdendum
PDE     Partial Differential Equation
PDES    Product Data Exchange Specifications
PDF     Program Development Facility
PDL     Page Description Language
PDL     Program Design Language
PDN     Public Data Network
PDP     Plasma Display Panel
PDP     Programmed Data Processor
PDP     Programmed Data Processor [DEC]
PDQ     Pretty Damned Quick
PDS     Premises Distribution System [AT&T]
PDT     Pacific Daylight Time
PE      Phase Encoded
PE      Physical Education
PE      Prince Edward island
PE      Printer's Error
PE      Professional Engineer
PE      Protestant Episcopal
PEI     Prince Edward Island
PEP     Productivity Enhancement Project
PEPE    Pepe Est Presque Emacs
PERL    Pathologically Eclectic Rubbish Lister
PERL    Practical Extraction and Report Language
PEX     Phigs/phigs+ Extension to X
PFC     Plasma Fusion Center [MIT]
PG      Parental Guidance (suggested) [Movie rating]
PGA     Professional Graphics Adapter
PGA     Pure Grain Alcohol
PHA     Pulse Height Analyzer (or Analysis)
PHIGS   Programmers Hierarchical Interactive Graphics System
PHS     Public Health Service
PhysRev Physical Review Journal   - Phys Rev
PI      Principal Investigator
PI      Priority Interrupt
PI      Private Investigator
PIC     Plastic/Polyethelene Insulated Cable [Telephony]
PIC     Position Independant Code
PIF     Paid In Full
PIT     Principal, Interest, and Taxes
PIXEL   PIcture ELement
PLA     Programmable Logic Array
PLATO   Programmed Learning for Automated Teaching Operations (U. Ill., early '70s)
PLC     Programmable Logic Controller
PLCC    Plastic Leaded Chip Carrier
PLL     Phase-Locked Loop
PLM     Programming Language for Microcomputers
PLO     Palestine (sic?) Liberation Organization (?)
PLO     Please Leave On
PLSS    Portable Life Support System [Space]
PM      PayMaster
PM      Police Magistrate
PM      Post Meridiem
PM      Post Meridiem (after noon)
PM      PostMaster
PM      PostMortem
PM      Pressurized Module [Space]
PM      Preventive Maintenance
PM      Prime Minister
PM      Provost Marshal
PMC     Permanently Manned Capability [Space]
PMIRR   Pressure Modulated InfraRed Radiometer (on Mars Observer) [Space]
PMO     Prime Minister's Office
PMOS    P channel Metal Oxide Semiconductor (P-MOS) (see MOS)
PMS     PreMenstrual Syndrome
PMT     PhotoMultiplier Tube
PM/X    Presentation Manager for X windows
PN      Promissory Note
PNP     Positive-Negative-Positive (transistor)
PO      Petty Officer
PO      Post Office
PO      Postal Order
PO      Purchase Order
POC     Port Of Call
POD     Pay On Delivery
POE     Port Of Embarkation
POE     Port Of Entry
POGO    Polar Orbiting Geophysical Observatory
POM     Phase Of Moon
POP     Point of Presence [Telephony]
POP     Post Office Protocol [Networking] (esp. TCP/IP)
POPS    Paperless Order Processing System
POR     Price On Request
POS     Point Of Sale
POS     Professional Operating System [DEC]
POSI    Promoting conference for OSI
POSIX   Portable Operating System for unIX
POSIX   Portable Operating System Interface
POTS    Plain Old Telephone Service [Telephony]
POTV    Personnel Orbit Transfer Vehicle [Space]
POV     Point Of View
POW     Prisoner Of War
PP      Parcel Post
PP      Past Participle
PP      Post Pay (payphone) [Telephony]
PP      Primary Point
PPB     Parts Per Billion
PPC     Pour Prendre Conge' (to take leave)
PPCS    Person to Person, Collect, Special [Telephony]
PPM     Parts Per Million
PPN     Parameterized Post-Newtonian formalism for general relativity
PPN     Project Programmer Number
PPP     Point-to-Point Protocol (successor to SLIP (q.v.))
pps     Packets per Second
PPS     PostPostScriptum
PPT     Parts Per Trillion
PPT     Pulse Pair Timing
PPT     Punched Paper Tape
PQ      Province of Quebec
PR      PayRoll
PR      Public Relations
PR      Puerto Rico
PRC     Planning Research Corporation
PREPnet Pennsylvania Research & Economic Partnership Network
PRI     Primary Rate Interface (ISDN) [Telephony]
PRN     pro re nata [Medicine] (as needed?)
PROFS   PRofessional OFfice System [IBM]
PROM    Programmable Read-Only Memory
PS      PicoSecond
PS      PostScript
PS      PostScriptum
PS      Power Steering
PS      Power Supply
PS      Proposed Standard
PS      Public School
PSA     Problem Statement Analyzer
PSC     Pittsburgh Supercomputer Center
PSC     Polar Stratospheric Clouds
PSDN    Public Switched Data Network [Telephony]
PSDS    Public Switched Digital Service [Telephony, AT&T]
PSE     Programming Support Environment
PSF     Point Spread Function [Space]
PSG     Platoon SerGeant
PSI     Performance Systems International [Corporate name, Networking]
PSI     Power Systems, Incorporated [Corporate name, Model Railroading]
PSK     Phase Shift Keying
PSL     Problem Statement Language
PSN     Packet Switch Node [ARPANET/MILNET] (replaced IMP)
PSR     Product Specific Realizations
PSR     PulSaR [Space]
PSS     (unknown to me, but something in the UK environment)
PST     Pacific Standard Time
PSTN    Public Switched Telephone Network
PT      Pacific Time
PT      Patrol Torpedo (as in PT boat)
PT      Physical Therapy
PT      Physical Training
PTA     Parent-Teacher Association
PTD     Parallel Transfer Disk
PTL     Praise The Lord (ministry)
PTN     Plant Test Number [Telephony] (actual number assigned for 800 service)
PTO     Patent and Trademark Office
PTO     Please Turn Over
PTO     Power Take-Off
PTT     Post, Telephone and Telegraph administration
PTV     Passenger Transport Vehicle [Space]
PUC     Public Utilities Commision
PV      Photovoltaic [Space]
PVC     Permanent Virtual Circuit (see also VC)
PVC     Poly-Vinyl Chloride
PVO     Pioneer Venus Orbiter [Space]
PW      Prisoner of War (usually POW)
PWG     Permanent Working Group
PX      Post eXchange (see BX)
QAM     Quadrature Amplitude Modulation
QC      Quality Control
QC      Queen's Counsel (KC when queen reigning)
QD      Quaque Die (daily) [Medicine]
QDA     Quantity Discount Agreement
QED     Quod Erat Demonstrandum (which was to be demonstrated) [Latin]
QEF     Quod Erat Faciendum (which was to be done) [Latin]
QEI     Quod Erat Inveniendum (which was to be found out) [Latin]
QET     Quantum Effect Transistor
QIC     Quarter-Inch Cartridge
QID     Quater In Die (four times a day) [Medicine]
QLI     Query Language Interpreter
QM      QuarterMaster
QMC     QuarterMaster Corps
QMF     Query Management Facility
QMG     QuarterMaster General
QMS     Quality Micro Systems [Corporate name]
QNS     Quantity Not Sufficient
QSO     Quasi-Stellar Object [Space]
q.v.    ???? (Latin(?): which see)
QWERTY  first six keys from left on top alphabetic row of standard keyboard
R       Restricted [Movie rating]
R       Rolemaster
RA      Regular Army
RA      Research Assistant
RA      Royal Academy
RAAF    Royal Australian Air Force
RACE    Random Access Card Equipment
RACEP   Random Access and Correlation for Extended Performance
RAD     Radiation Absorbed Dose
RAD     Rapid Access Disk
RADAR   RAdio Detection And Ranging
RADM    Rear ADMiral
RAF     Royal Air Force
RAM     Random Access Memory (R/W)
RAM     Red Academicia de Mexico (Mexican Academic Network)
RARDE   Royal Armaments Research and Development Establishment
RARE    R\'eseaux Associ\'es pour la Recherche Europ\'eenne (the European Organization of Research Networks)
RAS     Reliability, Availability, and Serviceability
RASC    Residence Account Service Center
RATS    Radio Amateur Telecommunications Society
R&B     Rhythm and Blues (commonly R and B)
RBC     Red Blood Count
RBI     Runs Batted In
RBOC    Regional Bell Operating Company
RC      Red Cross
RC      Regional Center
RC      Resistor-Capacitor circuit (as in filters)
RC      Roman Catholic
RCA     Radio Corporation of America [Corporate name]
RCAF    Royal Canadian Air Force
RCAS    Reserve Component Automation System
RCC     Radio Common Carrier
RCMP    Royal Canadian Mounted Police
RCS     Reaction Control System [Space]
R&D     Research and Development (commonly R and D)
RD      Rural Delivery
RDA     Remote Data Access
RDBMS   Relational DataBase Management System
RDF     Radio Direction Finding
REA     Rail Express Agency
RECON   Reconnaissance
REM     Rapid Eye Movement
REO     R. E. Olds
REO     Removable, Erasable, Optical
RETMA   Radio {something(equipment?)?} {something?} Manufacturers' Association (????)
REXX    Restructured EXtended eXecutor
RF      Radio Frequency
RF      Radio Frequency [Space]
RFC     Request For Comments (ala ARPA Internet)
RFD     Rehoboth (MA) Fire Department
RFD     Rural Free Delivery
RFI     Radio Frequency Interference
RFI     Radio Frequency Interference [Space]
RFP     Request for Proposal
RFQ     Request for Quote
RFS     Remote File System
RGB     Red Green Blue
RGP     Raster Graphics Processor
RH      Right Hand
RHC     Regional (Bell) Holding Company
RHS     Right Hand Side
RI      Rhode Island
RIACS   Research Institute for Advanced Computer Science (NASA)
RIACS   Research Institute for Advanced Computer Science [Space]
RIAS    Radio In the American Sector, berlin
RIF     Reading Is Fundamental
RIF     Reduction In Force
RILM    Repertoire International de Literature Musicale
RIP     Rest In Peace (or Requiescat In Pace : latin)
RIP     Routing Interchange Protocol
RIPE    R\'eseaux IP Europ\'eenne (European IP Networks) (of RARE, q.v.)
RISC    Reduced Instruction Set Computer
RITA    Recognition of Information Technology Achievement award
RJE     Remote Job Entry
RLC     Resistor Inductor Capacitor
RLG     Research Libraries Group
RLIN    Research Libraries Information Network (run by RLG (q.v.))
RLL     Run Length Limited
RMA     Radio Manufacturers' Association
RMA     Return Materials Authorization
RMATS   Remote Maintenance Administration and Traffic System [Telephony]
RMS     Remote Manipulator System [Space]
RMS     Richard M. Stallman
RMS     Root Mean Square
RMS     Royal Mail Ship
RN      Registered Nurse
RN      Royal Navy
RNA     RiboNucleic Acid
RNGC    Revised New General Catalog [Space]
RNZAF   Royal New Zealand Air Force
ROFF    Run-OFF
ROG     Receipt Of Goods
ROM     Range Of Motion [Medicine]
ROM     Read-Only Memory
ROM     Rupture Of Membrane (as in birth)
ROSAT   ROentgen SATellite [Space]
ROSE    RATS (q.v.) Open Systems Environment
ROSE    Remote Operations Service Entity (per ISO/CCITT layer 7)
ROTC    Reserve Officers' Training Corps
ROTS    Rotary Out Trunks Selectors
ROYGBIV Red, Orange, Yellow, Green, Blue, Indigo, Violet
RPC     Remote Procedure Call
RPG     RePort Generator
RPG     Role Playing Game
RPI     Rensselaer Polytechnic Institute
RPM     Revolutions Per Minute
RPN     Reverse Polish Notation
RPO     Railway Post Office
RPS     Revolutions Per Second
RPV     Remotely Piloted Vehicle
RQ      RuneQuest
RR      RailRoad
RR      Route Relay
RR      Rural Route
RRO     Rate and Route Operator [Telephony]
RS      Recommended Standard (EIA)
RS      Recording Secretary
RS      Revised Status
RS      Right Side
RS      Royal Society
RSCS    Remote Spooling Communications Subsystem
RSFSR   Russian Soviet Federated Socialist Republic
RSN     Real Soon Now
RSU     Remote Switching Unit
RSV     Revised Standard Edition
RSVP    Repondez S'il Vous Plait (please reply)
RSWC    Right Side up With Care
RT      RadioTelephone
RT      RealTime
RTA     Remote Trunk Arrangement [Telephony]
RTAC    Regional Technical Assistance Center [Telephony]
RTF     Rich Text Format
RTFM    Read The @!# Manual
RTFM    Read The F***ing Manual
RTG     Radioisotope Thermoelectric Generator
RTG     Radioisotope Thermoelectric Generator [Space]
RTLS    Return To Launch Site (Shuttle abort mode) [NASA, Shuttle, Space]
RTR     Ready to Run [Model Railroading]
RTR     Reel-To-Reel
RTS     Request To Send (EIA RS-232-C)
RTTY    Radio Teletype
RU      Receive Unit
RVD     Remote Virtual Disk [MIT]
RW      Right Worshipful
RW      Right Worthy
RX      Receive
Ry      Railway
S       South
S       Supplement
SA      Salvation Army
SA      Seaman Apprentice
SA      Service Assistant
SA      Sex Appeal
SA      Sine Anno (without date)
SA      South Africa
SA      South America
SA      Subject to Approval
SAA     South Atlantic Anomaly
SAA     South Atlantic Anomaly [Space]
SAA     Systems Application Architecture
SAC     Special Area Code [Telephony] (represent services, not places)
SAC     Strategic Air Command (see TAC)
SAC     Strategic Air Command [US military]
SADD    Students Against Drunk Driving
SAFENET Survivable Adaptable Fiberoptic Embedded Network [US Navy]
SAM     Surface to Air Missile
SAM     Surface-to-Air Missile
SAMA    Step-by-step Automatic Message Accounting [Telephony]
SAMPEX  Solar Anomalous and Magnetospheric Particle EXplorer [Space]
SAMTO   Space And Missile Test Organization [Space]
SAO     Smithsonian Astrophysical Observatory [Space]
SAP     Second Audio Program
SAP     Service Access Point [OSI, Networking]
SAR     Search And Rescue
SAR     Synthetic Aperture Radar
SARA    Satellite pour Astronomie Radio Amateur [Space]
SARA    Stichting Academisch Rekencentrum Amsterdam (Amsterdam Universities Computing Center)
SAREX   Search and Rescue Exercise [Space]
SAREX   Shuttle Amateur Radio Experiment [Space]
SARTS   Switched Access Remote Test System
SAS     Small Astronomy Satellite
SAS     Space Activity Suit [Space]
SASE    Self-Addressed Stamped Envelope
SASI    Shugart Associates Systems Interface
SAT     Satellite [Space]
SAW     Surface Acoustic Wave
SBA     Small Business Administration
SC      Secondary Channel
SC      Sectional Center
S&C     Skull & Crossbones
SC      South Carolina
S/C     SpaceCraft [Space]
SC      SubCommittee
SCA     Shuttle Carrier Aircraft [Space]
SCAD    Subsonic Cruise Armed Decoy
SCADC   Standard Central Air Data Computer
SCAME   SCreen oriented Anti-Misery Editor
SCAMP   Single-Chip A-series Mainframe Processor
SCAN    Switched Circuit Automatic Network
SCC     Specialized Common Carriers
SCC     Switching Control Center
SCCS    Source Code Control System
SCE     Signal Conversion Equipment
SCE     Structure Chart Editor
SCI     SpaceCraft Incorporated
SCIFI   SCIence FIction (often used pejoratively of what really isn't)
SCO     Santa Cruz Operation
SCOOPS  SCheme Object Oriented Programming System
SCOTS   Surveilance and Control Of Transmission Systems
SCSI    Small Computer Systems Interface
SCT     Schmidt-Cassegrain Telescope [Space]
SCUBA   Self Contained Underwater Breathing Apparatus
SCUD    Subsonic Cruise Unarmed Decoy
SD      South Dakota
SDB     Source(?) DeBugger
SDI     Standard Disk Interconnect [DEC]
SDI     Strategic Defense Initiative [Space, US Government]
SDIO    Strategic Defense Initiative Organization [Space, US Government]
SDLC    Synchronous Data Link Control [IBM]
SDM     Sub-rate Data Multiplexer
SDN     Software Defined Network [Telephony, AT&T]
SDN     System Development Network (Korea)
SDO     Staff Duty Officer
SDSC    San Diego Supercomputer Center
SDV     Shuttle Derived Vehicle [Space]
SE      Service Engineer (see also CE, FE)
SE      South East
SEATO   SouthEast Asia Treaty Organization
SEC     Security Exchange Commission
SECNAV  SECretary of the NAVy
SED     Stream EDitor
SEI     Software Engineering Institute (Carnegie Mellon)
SEI     Space Exploration Initiative [Space]
SEL     Software Engineering Laboratory
SEM     Scanning Electron Microscope
SEST    Swedish-European Submillimeter Telescope [Space]
SETI    Search for Extra Terrestrial Intelligence [Space]
SETI    Search for ExtraTerrestrial Intelligence [Space]
SF      San Francisco
SF      Science Fiction; Speculative Fiction
SF      Standard Form
SF      Star Frontiers
SFRPG   Science Fiction Role Playing Game
SG      StarGuard
SG      SubGroup
SGML    Standard Generalized Markup Language
SHAPE   Supreme Headquarters Allied Powers Europe
SHAR    SHell ARchiver
SHCD    Sherlock Holmes Consulting Detective
SHF     Super High Frequency (3-30GHz)
SHRPG   Super Hero Role Playing Game
SI      Staten Island
SIAM    Society for Industrial and Applied Mathematics
SID     Sudden Ionospheric Disturbance [Space]
SIG     Special Interest Group
SIGCAT  Special Interest Group for Cd-rom Applications Technology
SIMD    Single Instruction, Multiple Data
SIMM    Single In-line Memory Module
SIMM    System Integrated Memory Module
SINE    SINE is not EINE
SIPS    Satellite Imagery Processing System
SIR     Shuttle Imaging Radar [Space]
SIRTF   Space (formerly Shuttle) InfraRed Telescope Facility [Space]
SIRTF   Space Infrared Telescope Facility [Space]
SIS     Strategic Information System
SISCOM  Satellite Information System COMpany
SITA    Societe Internationale Telecommunications Aeronautiques
SJ      Society of Jesus
Skyhook Surface to space "elevator" transportation system [Space]
SL      Salvage Loss
SL      Space Launch [Space]
SL      SpaceLab [Space]
SLA     Special Libraries Association
SLA     Synchronous Line Adapter
SLAC    Stanford Linear Accelerator Center
SLAN    Sine Loco, Anno, (vel) Nomine (without place, year, or name)
SLAR    Side Looking Airborne Radar
SLAR    Side-Looking Airborne Radar [Space]
SLBM    Submarine Launched Ballistic Missiles
SLC     Space Launch Complex [Space]
SLC     Subscriber Loop Carrier [Telephony]
SLDC    Synchronous Data Link Control
SLIP    Serial Line Internet Protocol
SLIP    Serial Line IP (sometimes SL/IP) (see also PPP)
SLP     Super Long Play (VHS VCR)
SLS     Space(lab) Life Sciences [Space]
SM      Service Mark
SMA     Sergeant Major of the Army
SMA     Spectrum Manufacturers Association
SMC     Small Magellanic Cloud (see LMC)
SMC     Small Magellanic Cloud [Space]
SMD     Storage Module Device (interface standard for disk drives)
SMD     Surface Mounted Devices
SMDR    Station Message Detail Recording [Telephony]
SMDS    Switched Multi-megabit Data Service [Telephony, Networking]
SME     Solar Mesosphere Explorer [Space]
SMEGMA  Sophisticated Modern Editor with Gloriously Magnificent Abilities
SMERSH  Abbr. of Russian phrase meaning "Death to the spies."
SMEX    SMall EXplorers [Space]
SMILS   Sonobuoy Missile Impact Location System
SMM     Solar Maximum Mission (satellite 1980-1989) [Space]
SMTP    Simple Mail Transfer Protocol
SMU     Southeastern Massachusetts University
SMU     Southern Methodist University
SN      Science News [Periodical]
SN      Serial Number
SN      Super Nova
SN      SuperNova (e.g., SN1987A) [Space]
SNA     Systems Network Architecture [IBM]
SNADS   SNA Distribution Services
SNAFU   Situation Normal -- All Fouled Up (also more profane versions)
SNAP    Shipboard Non-tactical Automated data Processing program
SNAP    Sub Network Access Protocol [OSI, Networking]
SNCF    Societe National des Chemins de Fer (French National Railways)
SNF     Server-Natural Format
SNMP    Simple Network Management Protocol [TCP/IP]
SNOBOL  StriNg Oriented symbOLic Language
SNPA    SubNetwork Point of Attachment
SNR     Signal to Noise Ratio
SNR     Signal to Noise Ratio [Space]
SNR     SuperNova Remnant [Space]
SNU     Solar Neutrino Units [Space]
SO      Seller's Option
SO      Significant Other
SO      Space Opera
SO      Strike Out
SOAP    Symbolic Optimizing Assembler Program
SOFIA   Stratospheric Observatory For Infrared Astronomy [Space]
SOH     Start Of Header, ASCII control character (dec=01,control-A)
SOHIO   Standard Oil of oHIO [Corporate name]
SOHO    SOlar Heliospheric Observatory [Space]
SOL     Short on Landing (or, colloquially, Shit Out of Luck)
SONAR   SOund Detection And Ranging
SONET   Synchronous Optical Network [Telephony]
SOP     Standard Operating Procedure
SOS     Save Our Souls (International standard distress call, Morse ...---...)
SOS     Silicon On Sapphire
SOS     Son of Stopgap (editor) [DEC]
SP      Shore Patrol
SP      Short Play (VHS VCR)
s.p.    sine prole (Latin: without issue) [Genealogy]
SP      Southern Pacific [Corporate name, Railroading]
SP      Stack Pointer
SP      Star Patrol
SPA     Software Publishers Association
SPAG    Standards Promotion and Applications Group
SPAN    Space Physics and Analysis Network [NASA] (DECnet)
SPAN    Space Physics and Analysis Network [Space]
SPAR    Stock Points Adp Replacement
SPARC   Scalable Processor ARChitecture
SPARC   Standards, Planning, And Requirements Committee
SPAWAR  naval SPAce and WARfare command
SPC     Software Productivity Consortium
SPCA    Society for the Prevention of Cruelty to Animals
SPCC    Society for the Prevention of Cruelty to Children
SPDM    Special Purpose Dextrous Manipulator [Space]
SPEC    Systems Performance Evaluation Cooperative
SPITBOL SPeedy ImplemenTation of snoBOL
SPNI    Society for the Protection of Nature in Israel
SPOT    Systeme Probatoire pour l'Observation de la Terre [Space]
SPS     Solar Power Satellite [Space]
SPUR    Systech Pluraxial Unplug Repeater
SQE     Signal Quality Error (IEEE 802.3, eqv to D/I/X "Collision Presence Test") [Ethernet]
SQIID   Simultaneous Quad Infrared Imaging Device (at NOAO)
SQL     Structured Query Language
SQUID   Superconducting QUantum Interference Device
SRAM    Short Range Attack Missile
SRAM    Static RAM
SRB     Solid (fuel) Rocket Booster [Space]
SRG     Short and Ring Ground (test) [Telephony]
SRI     Stanford Research Institute
SRM     Solid Rocket Motor [Space]
SRO     Standing Room Only
SS7     Signalling System #7 [Telephony]
SSA     Social Security Administration [US Government]
SSB     Single Side Band
SSC     Superconducting Super Collider
SSE     South-SouthEast
SSF     Space Station Fred (er, Freedom) [Space]
SSF     Space Station Freedom [NASA, Space]
SSFF    Showcase Software Factory of the Future
SSG     Staff SerGeant
SSI     Small Scale Integration
SSI     Solid-State Imager (on Galileo) [Space]
SSI     Space Services Incorporated [Corporate name, Space]
SSI     Space Studies Institute [Space]
SSI     Supplemental Security Income
SSME    Space Shuttle Main Engine [Space]
SSPF    Space Station Processing Facility [Space]
SSPS    Satellite Solar Power Station [Space]
SSR     Secondary Surveillance Radar
SSR     Soviet Socialist Republic
SSRMS   Space Station Remote Manipulator System [Space]
SST     Spectroscopic Survey Telescope [Space]
SST     SuperSonic Transport [Space]
SSTO    Single Stage To Orbit [Space]
SSTV    Slow Scan TeleVision
SSW     South-SouthWest
ST      Short Ton
STARS   Software Technology for Adaptable, Reliable Systems
STD     Sacrae Theologiae Doctor (doctor of sacred theology)
STD     Sexually Transmitted Disease (replaces VD)
STD     State Transition Diagram
STD     Subscriber Trunk Dialing (British, and elsewhere; equiv. DDD in USA)
STI     Standard Tape Interconnect [DEC]
STILO   Scientific and Technical Intelligence Liaison Office
STIS    Space Telescope Imaging Spectrometer (to replace FOC and GHRS) [Space]
STL     St. Louis (airport designation)
STN     SuperTwisted Nematic
STOL    Short TakeOff and Landing
STP     Shielded Twisted Pair [Telecom, Networking]
STP     Software Through Pictures
STP     Standard Temperature and Pressure (see NTP)
STRPG   Star Trek:  The Role-Playing Game
STS     Space Transportation System (space shuttle) [NASA]
STScI   Space Telescope Science Institute [Space]
STV     Single Transferable Vote
STV     Space Transfer Vehicle [Space]
SUM     Symantec Utilities for Macintosh
SUN     Stanford University Network
SUN     SUN MicroSystems Computer (not an Acronym) [Corporate name]
SUNOCO  SUN Oil COmpany [Corporate name]
SUNY    State University of New York
SURAnet Southeastern Universities Research Association Network
SVID    System V Interface Definition
SW      South West
SW      SuperWorld
SWAS    Submillimeter Wave Astronomy Satellite [Space]
SWBT    South Western Bell Telephone [Telephony]
SWF     ShortWave Fading [Space]
SWIFT   Society for Worldwide Interbank Financial Communications
SWS     Scientific Workstation Support
SXS     Step by Step switching [Telephony]
T       Traveler
T1      1.544Mbps [Telephony], one of the basic signalling systems 24x64Kb
T3      45Mbps (eq 28 T1 channels) [Telephony]
TA      Teaching Assistant
TAC     Tactical Air Command (see SAC)
TAC     Terminal Access Controller [ARPANET/MILNET] (replaced TIP)
TACACS  Terminal Access Controller Access Control System [ARPANET/MILNET]
TACCS   Tactical Army Combat service support Computer System
TAE     Transportable Applications Environment
TAL     Trans-Atlantic Abort Landing [NASA, Shuttle]
TAL     Transatlantic Abort Landing (Shuttle abort plan) [Space]
TANSTAAFL       There Ain't No Such Thing As A Free Lunch
TAR     Tape ARchiver
TASI    Time Assign{ment,ed} Speech Interpolation [Telephony]
TAU     Thousand Astronomical Units [Space]
TB      TuBerculosis
TBA     To Be Announced
TBD     To Be Determined
TBD     To Be Done
TC      Teachers College
TCA     Terminal Controlled Airspace
TCP     Transmission Control Protocol
TCP/IP  Transmission Control Protocol/Internet Protocol
TCS     Thermal Control System [Space]
TCSEC   Trusted Computer System Evaluation Criteria (orange book)
TCT     To Challenge Tomorrow
TD      Tardive Dyskinesia
TD      TouchDown
TD      Treasury Department
TDCC    Transportation Data Coordinating Committee
TDE     Transition Diagram Editor
TDI     Trusted Database Interpretation
TDM     Time-Division Multiplexer
TDR     Time Domain Reflectometer
TDRS    Tracking and Data Relay Satellite [Space]
TDRSS   Tracking and Data Relay Satellite System [Space]
TDY     Temporary DutY
TECO    Tape Editor and COrrector
TECO    Text Editor and COrrector
TEFLON  polyTEtraFLuOrethyleNe
TES     Thermal Emission Spectrometer (on Mars Observer) [Space]
TFP     Tops Filing Protocol
TFS     Translucent File System
TFT     The Fantasy Trip
TFT     Thin Film Transistor
TG      Thieves' Guild
TGV     Tres Grande Vitesse (French, Very High Speed) [Railroading]
TGV     Two Guys and a VAX (humorous variant) [Corporate name]
THIEF   THief Isn't Even Fine
THIEF   This Here Isn't Even Fine
THOR    Tandy High-intensity Optical Recording
TI      Texas Instruments
TIA     Thanks In Advance [Net jargon]
TIA     Transient Ischemic Attack
TIC     TermInfo Compiler
TID     Ter In Die (three times a day)
TID     Transaction ID
TIFF    Tag Image File Format
TIP     Terminal Interface Processor [ARPANET/MILNET] (replaced by TAC)
TIS     Trusted Information Systems [Corporate name]
TISN    Tokyo International Science Network (Japan)
TKO     Technical Knock Out [Boxing]
TL      Total Loss
TLA     Three Letter Acronym
TLC     Tender Loving Care
TLI     Transort-Level Interface
TM      TradeMark
TMA     Tycho Magnetic Anomaly (movie 2001)
TMAC    Treasury department's Multiuser Acquisition Contract
TMIS    Telecommunications Management Information System
TMO     Telephone Money Order
TMP     The Morrow Project
TMRC    Tech Model Railroad Club [MIT]
TMRC    Transportation Modeling Research Center (TMRC {above} alter ego)
TN      Tennessee
TN      Twisted Nematic
TNC     Threaded Neill Concelman (connector) [Electronics] (see also BNC)
TNF     Tumor Necrosis Factor [Biology, Medicine]
TNP     Tech Nickel Plate (RR) [TMRC]
TNT     TriNitro Toluene
TO      Telegraph Office
TO      Turn Over
TODS    Transactions on Database Systems (ACM)
TOMS    Total Ozone Mapping Spectrometer [Space]
TOMS    Transactions on Mathematical Software (ACM)
TOOIS   Transactions on Office Information Systems (ACM)
TOP     Technical Office Protocol
TOPLAS  Transactions on Programming Languages and Systems (ACM)
TOPS    Traffic Operator Position System [Telephony]
TOPSMP  Traffic Operator Position System Multipurpose [Telephony]
TORES   Text ORiented Editing System
TOS     Transfer Orbit Stage [Space]
TOW     Tube launched, Optically tracked, and Wire guided
TOY     Time Of Year (clock)
TP      Transaction Processing
TP      Transport Protocol (ISO/CCITT Transport Services (TP0-TP4); like TCP)
TP4     Transport Protocol, class 4 [ISO]
TPC     The Phone Company (from classic movie: _The President's Analyst_)
TPI     Tracks Per Inch
TPO     Traveling Post Office
TPP     TetraarylPorPhyrin
TPS     Technical Publishing Software
TPS     TeleProcessing Services
TPS     Thermal Protection System [Space]
TR      Tech Report (at least at LCS (q.v.), maybe others)
TR      Technical Reference [Bell, Telephony]
TRG     Tip and Ring Ground (test) [Telephony]
TROFF   Text RunOFF, text formatter
TRUSIX  TRUSted unIX
TRW     Thompson, Ramo, and Woolridge
TS      Top Secret
TSAP    Transport Service Access Point [OSI, Networking]
TSD     Total System Design
TSP     Teleprocessing Services Program
TSP     Thrift Savings Plan
TSP     Time Synchronization Protocol
TSP     TriSodium Phosphate
TSR     TSR (Fortune 500 Company that manufactures Dungeons & Dragons)
TSS     Tethered Satellite System [Space]
TSTO    Two Stage to Orbit [Space]
T&T     Tunnels & Trolls
TTFN    Tah Tah, For Now
TTL     Transistor Transistor Logic
TTMA    Tennessee Tech Microcomputer Association
TTU     Tennessee Technological University
TTY     TeleTYpe
TUNIS   Toronto UNIversity System
TV      TeleVision
TVA     Tennessee Valley Authority
TW      Thieves' World
TWA     Trans World Airlines [Corporate name]
TWB     Terrestrial WideBand [Networking, DARPA]
TWIMC   To Whom It May Concern
TWT     Traveling Wave Tube
TWX     TeletypeWriter eXchange
TX      Texas
Tx      Transmit
u       (representing the greek mu) - micro
U       Universe
UA      United Artists
UAR     United Arab Republic
UAR     User Action Routine
UARS    Upper Atmosphere Research Satellite [Space]
UART    Universal Asynchronous Receiver Transmitter
UBA     UniBus Adapter [DEC]
UBC     Universal Bibliographic Control
UBC     University of British Columbia
UBM     Unpressurized Berthing Mechanism [Space]
UCAR    University Corporation for Atmospheric Research
UCB     University of California at Berkeley
UCD     Uniform Call Distributor [Telephony]
UCD     University of California at Davis
UCI     University of California at Irvine
UCL     University College London
UCLA    University of California at Los Angeles
UCR     University of California at Riverside
UCSB    University of California at Santa Barbara
UCSC    University of California at Santa Cruz
UCSD    University of California at San Diego
UCSF    University of California at San Francisco
UDB     Unified DataBase
UDMH    Unsymmetrical DiMethyl Hydrazine [Space]
UDP     User Datagram Protocol
UEC     User Environment Component
UFO     Unidentified Flying Object [Space]
UGC     Uppsala General Catalog [Space]
UH      Upper Half
UHF     Ultra High Frequency (300-3000MHz)
UID     Unique IDentifier
UID     User IDentification [UNIX]
UIMS    User Interface Management System
UIT     Ultraviolet Imaging Telescope (Astro package) [Space]
UIUC    University of Illinois at Urbana-Champaign
UK      United Kingdom
UKST    United Kingdom Schmidt Telescope [Space]
UL      Underwriters Laboratory
ULANA   Unified Local-Area Network Architecture
UMOC    Ugliest Man On Campus [MIT]
UMT     Universal Military Training
UN      United Nations
UNESCO  United Nations Educational, Scientific, & Cultural Organization
UNICEF  United Nations International Children's Emergency Fund (now United Nat. Child. Fund)
UNICS   UNiplex Information Computer Services
UNIX    Not an acronym at all.  Was a joke on MIT's MULTICS.
UNMA    Unified Network Management Architecture [AT&T]
UNO     United Nations Organization
UP      Union Pacific [Railroading, Corporate name]
UPC     Universal Product Code
UPI     United Press International
UPI     United Press International [Corporate name]
UPS     Uninterruptible Power Supply
UPS     United Parcel Service [Corporate name]
UR      University of Rochester
URI     University of Rhode Island
US      United States (of America)
USA     Union of South Africa
USA     United States Army
USA     United States of America
USAF    United States Air Force
USAFA   United States Air Force Academy (in Colorado Springs)
USAN    University Satellite Network
USB     Upper Side Band
USC     University of Southern California
USCG    United States Coast Guard
USDA    United States Department of Agriculture
USES    United States Employment Service
USFL    United States Football League
USGS    United States Geological Survey
USIA    United States Information Agency
USM     United States Mail
USMC    United States Marine Corps
USMP    United States Microgravity Payload [Space]
USN     United States Navy
USO     United Service Organizations
USO     Unix Software Operation
USP     United States Pharmacopeia
USPS    United States Postal Service
USR     User Service Routines
USS     United States Ship
USSR    Union of Soviet Socialist Republics
USSS    User Services and Systems Support
USW     Und So Weiter
UT      Universal Time (a.k.a. GMT, UTC, or Zulu Time)
UT      University of Tennessee
UT      University of Texas
UT      UTah
UTC     Coordinated Universal Time (a.k.a. UT)
UTC     Universal Coordinated Time (a.k.a. UT)
UTnet   University of Texas Network
UTP     Unshielded Twisted Pair [Telecom, Networking]
UUCP    UNIX-to-UNIX Copy Program
UUG     Unix User Group
UV      UltraViolet
UVS     UltraViolet Spectrometer
UW      UnderWriter
UW      Univ of Wisconsin
VA      Veterans Administration
VA      Virginia
VAB     Vehicle Assembly Building (formerly Vertical Assembly Building) [Space]
VAFB    Vandenberg Air Force Base [Space]
VAN     Value Added Network (e.g. Tymnet, Telenet, etc)
VANS    Value-Added Network Services
VAR     Value Added Remarketer (reseller)
VASI    Visual Approach Slope Indicator
VAT     Value Added Tax
VAX     Virtual Address eXtended
VAXBI   VAX Bus Interconnect
VC      Viet Cong
VC      Virtual Circuit
Vcc     Voltage (Common Cathode?)
VCM     Voice Coil Motor
VCO     Voltage Controlled Oscillator
VCR     VideoCassette Recorder
VCU     Virginia Commonwealth University
VD      Venereal Disease (see also STD)
VDFM    Virtual Disk File Manager
VDI     Virtual Device Interface
VDM     Vienna Development Method
VDM     Virtual Device Metafile
VDT     Video Display Terminal
VEEGA   Venus-Earth-Earth Gravity Assist (Galileo flight path) [Space]
VF      Video Frequency
VF      Voice Frequency
VFO     Variable Frequency Oscillator
VFR     Visual Flight Rules [Aviation]
VFW     Veterans of Foreign Wars
VFW     Volunteer Fire Department
VG      Very Good
VG      Vicar-General
VGA     Video Graphics Array
Vgg     Voltage (Gate to Ground?)
V&H     Vertical and Horizontal (CO coordinate tape) [Telephony]
VHDL    Vhsic Hardware Description Language
VHF     Very High Frequency (30-300MHz)
VHS     Video Home System (VCR)
VHSIC   Very High Speed Integrated Circuit
VI      VIsual editor
VIABLE  Vertical Installation Automation BaseLinE
VILE    VI Like Emacs
VINE    Vine Is Not Emacs
VIP     Very Important Person
VISTA   Volunteers In Service To America
VITA    Vme International Trade Association
VJ      Video Jockey
VL      Vulgar Latin
VLA     Very Large Array [Space]
VLBA    Very Long Baseline Array [Space]
VLBI    Very Long Baseline Interferometry [Space]
VLF     Very Low Frequency (3-30KHz)
VLIW    Very Long Instruction Word
VLSI    Very Large Scale Integration
VLT     Very Large Telescope [Space]
VM      Virtual Memory
VM/CMS  Virtual Machine/Conversational Monitor System
VMM     Virtual Memory Manager
VMOS    Vertical Metal Oxide Semiconductor (V-MOS) (see MOS)
VMR     Vertical Market Reseller
VMS     Vertical Motion Simulator [Space]
VMS     Virtual Memory System [DEC]
VOA     Voice Of America
VOIR    Venus Orbiting Imaging Radar (superseded by VRM) [Space]
VOIS    Voice-Operated Information System
VOQ     Visiting Officer's Quarters
VPI&SU  Virginia Polytechnic Institute and State University
VRC     Vertical Redundancy Character
VRM     Venus Radar Mapper (now called Magellan) [Space]
VRM     Virtual Resource Manager
VSAT    Very Small Aperture Terminal (satellite dish)
VSX     X/open Verification Suite
VTAM    Virtual Telecommunications Access Method [IBM]
VTOC    Volume Table Of Contents
VTOL    Vertical TakeOff and Landing
VTR     VideoTape Recorder
VUP     Vax Unit of Performance
V&V     Villains & Vigilantes
VVSS    Vertical Volute Spring Suspension
W       West
W       Width
WA      Washington
WA      Western Australia
WAC     Womens Air Corps
WAIS    Wide Area Information Server
WARC    World Administrative Conference
WATS    Wide Area Telephone Service
WB      Water Ballast
WB      WayBill
WBC     White Blood Cells
WC      Water Closet
WC      Without Charge
WCTU    Women's Christian Temperance Union
WD      White Dwarf [Space]
w.d.    will dated [Genealogy]
WECo    Western Electric Company [AT&T] (manufacturing arm of AT&T)
WFPC    Wide Field / Planetary Camera (on HST) [Space]
WFPCII  Replacement for WFPC [Space]
WG      Working Group
WH      WarHammer
WHBL    World Home Bible League
WHCA    White House Communications Agency [US Government]
WHO     World Health Organization
WI      Wisconsin
WIMP    Windows/Icons/Mouse Programming(?)
WIPP    (nuclear) Waste Isolation Pilot Plant [DOE]
WIS     WWMCCS Information System
WITS    Washington Interagency Telecommunications System
WIYN    Wisconsin / Indiana / Yale / NOAO telescope [Space]
WMSCR   Weather Message Switching Center Replacement
WOM     Write Only Memory
WOP     WithOut Papers [Immigration]
WOPR    War Operations Planned Response (from "Wargames" movie)
WORM    Write Once, Read Many times
WOW     Worlds of Wonder
w.p.    will proved [Genealogy]
WP      Word Processing
WP      Working Paper
WPI     Worcester Polytechnic Institute
WSI     Wafer Scale Integration
WSMR    White Sands Missile Range [Space]
WSW     West-SouthWest
WTR     Western Test Range [Space]
WU      Washington University
WU      Western Union
WUPPE   Wisconsin Ultraviolet PhotoPolarimter Experiment (Astro package) [Space]
WV      West Virginia
WW      World War
WWI     World War I
WWII    World War II
WWMCCS  World-Wide Military Command and Control System
WY      Wyoming
WYSIWIS What You See Is What I See
WYSIWYG What You See Is What You Get
XCF     eXperimental Computing Facility
XD      without Dividend
XDR     eXternal Data Representation
XFER    Transfer
XINU    XINU Is Not UNIX
XL      eXtra Large
XMM     X-ray Multi Mirror [Space]
XMTR    transMiTteR (the X is for trans)
XNS     Xerox Network Services
XO      eXecutive Officer
XOR     eXclusive OR (logical function)
XPORT   Transport
XSECT   cross SECTion
XTAL    crysTAL (another version of x for crys, see XMTR)
XUI     X-windows User Interface
XUV     eXtreme UltraViolet [Space]
YA      Yet Another
YACC    Yet Another Compiler Compiler
YB      YearBook
YMCA    Young Mens Christian Association
YMHA    Young Mens Hebrew Association
YOB     Year Of Birth
YP      Yellow Pages
YRS     Ysgarth Rules System
YSO     Young Stellar Object [Space]
YST     Yukon Standard Time
YT      Yukon Territory
YT      Yukon Time
YTD     Year To Date
YWCA    Young Womens Christian Association
YWHA    Young Womens Hebrew Association
Z       Zenith
Z       Zero
Z       Zulu (time)
ZB      Zero Beat
ZETA    Zero Energy Thermonuclear Assembly
ZGS     Zero Gradient Synchrotron
ZI      Zonal Index
ZIF     Zero Insertion Force (connector/socket)
ZIP     Zone Improvement Plan (US post office code)
ZK      barrage balloon (navy symbol)
ZMRI    Zinc Metals Research Institute
ZPG     Zero Population Growth
ZPRSN   Zurich Provisional Relative Sunspot Number
ZST     Zone Standard Time
ZT      Zone Time
ZWEI    Zwei Was Eine Initially