(EOL) Synonym for newline, derived perhaps from the original CDC6600 Pascal. Now rare, but widely recognised and occasionally used for brevity. Used in the example entry under BNF.
Out of context this would probably be (deliberately) ambiguous because different systems used different (combinations of) characters to mark the end of a line. Unix uses a newline (ASCII 10); DOS uses carriage return (ASCII 13), line feed (see CRLF) and the Macintosh uses carriage return.
See also EOF.