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Definition of knockout
(Entry 1 of 3)
b(1) : the termination of a boxing match when one boxer has been knocked down and is unable to rise and resume boxing within a specified time
(2) : technical knockout
c : a blow that knocks out an opponent
2 : a sensationally striking, appealing, or attractive person or thing
knockout
adjectiveDefinition of knockout (Entry 2 of 3)
1 : causing a knockout
a knockout blow
2 : sensationally striking, appealing, or attractive
a knockout dress
3 : having all or part of a gene eliminated or inactivated by genetic engineering
knockout mice predisposed to diabetes mellitus
knock out
verbknocked out; knocking out; knocks out
Definition of knock out (Entry 3 of 3)
1 : to produce roughly or hastily
2a(1) : to defeat (a boxing opponent) by a knockout
(2) : to make unconscious
the drug knocked him out
b : to make inoperative or useless
electricity was knocked out by the storm
c : to get rid of : eliminate knocked out illegal gambling
3 : to tire out : exhaust knocked themselves out with work
4 : to cause (an opposing pitcher) to be removed from a baseball game by a batting rally
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Time Traveler for knockout
The first known use of knockout was in 1818
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