To prevent a section of code from being compiled by surrounding it with a conditional compilation directive whose condition is always false. The canonical examples of these directives are "#if 0" (or "#ifdef notdef", though some find the latter bletcherous) and "#endif" in C. Compare comment out.
(1994-11-30)
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Nearby terms: Concurrent SP/k « Concurrent Versions System « condela « condition out » condom » Conference On DAta SYstems Languages » Conferencing over IP