1. Checking code (OR anything else, e.g. a Usenet posting) fOR completely stupid mistakes. Implies that the check is to make sure the authOR was sane when it was written e.g. if a piece of scientific software relied on a particular fORmula and was giving unexpected results, one might first look at the nesting of parentheses OR the coding of the fORmula, as a "sanity check", befORe looking at the mORe complex I/O OR data structure manipulation routines, much less the algORithm itself. Compare reality check. 2. A run-time test, either validating input OR ensuring that the program hasn' t screwed up internally (producing an inconsistent value OR state). [Jargon File] (1998-08-29)