a. The act of knocking out.
b. The state of being knocked out.
c. A blow that knocks out an opponent.
a. A victory in boxing in which one's opponent is unable to rise from the canvas within a specified time after being knocked down or is judged too injured to continue.
b. The act of winning a boxing match in this way: won the fight by a knockout.
3. Slang A strikingly attractive or impressive person or thing.
adj. also knock-out (nŏkout′)
1. Capable of knocking someone out: a knockout punch; knockout drops put in a drink.
2. Strikingly attractive or impressive.
3. Genetics Having a specific single gene inactivated or removed by genetic manipulation: knockout mice used in an experiment.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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