A dimension style override is a change made to the current dimension style. It is equivalent to changing a dimensioning system variable without changing the current dimension style. For example, if you change the color of extension lines in the Geometry dialog box, the current dimension style remains unchanged. However, the new value for color is stored in the DIMCLRE system variable. The next dimension you create will have extension lines in the new color. You can save the dimension style overrides as a new dimension style.
Some dimension characteristics are common to a drawing or to a style of dimensioning and are therefore suited to be permanent dimension style settings. Others generally apply on an individual basis and can be applied more effectively as overrides. For example, a drawing usually uses a single type of arrowhead, so it makes sense to define the arrowhead type as part of the dimension style. Suppression of extension lines, however, usually applies in individual cases only and is more suited to a dimension style override.
There are several ways to set up dimension style overrides. You can change options in the dialog boxes or change system variable settings on the command line. You reverse the override by returning the changed settings to their original values. The overrides apply to the dimension you are creating and all subsequent dimensions created with that dimension style until you reverse the override or make another dimension style current.
Example: A Dimension Style Override on the Command Line