/nok"owt'/ , n.
1. an act or instance of knocking out.
2. the state or fact of being knocked out.
3. a knockout blow.
4. Informal. a person or thing overwhelmingly attractive, appealing, or successful.
5. a panel in a casing, can, or box, esp. of metal or plastic, so designed that it can readily be removed, as by punching, hammering, or cutting, to provide an opening into the interior: a knockout in a junction box.
6. Mach. a device for knocking something loose, as finished work from a lathe chuck.
adj.
7. that knocks out: the knockout punch.
[ 1810-20; 1935-40 for def. 4; n., adj. use of v. phrase knock out ]