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The Usage Panel is a group of nearly 200 prominent scholars, creative writers, journalists, diplomats, and others in occupations requiring mastery of language. Annual surveys have gauged the acceptability of particular usages and grammatical constructions.
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. SlangA strikingly attractive or impressive person or thing.
adj.alsoknock-out(nŏkout′)
1. Capable of knocking someone out:a knockout punch; knockout drops put in a drink.
2. Strikingly attractive or impressive.
3. GeneticsHaving a specific single gene inactivated or removed by genetic manipulation:knockout mice used in an experiment.
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.