knockout

noun
knock·​out | \ ˈnäk-ˌau̇t \

Definition of knockout

 (Entry 1 of 3)

1a : the act of knocking out : the condition of being knocked out
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
c : a blow that knocks out an opponent
2 : a sensationally striking, appealing, or attractive person or thing

knockout

adjective

Definition 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

verb

Definition of knock out (Entry 3 of 3)

transitive verb

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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Examples of knockout in a Sentence

Noun

He won the match by a knockout. He scored a knockout in the fourth round. She's a real knockout in that dress.

Adjective

The Wimbledon tennis tournament is a knockout competition. a knockout sports car that's the talk of the neighborhood

Verb

the entire staff knocked itself out getting the project finished on time
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Recent Examples on the Web: Noun

Avangard could be used to attack American ballistic missile defenses, delivering a knockout blow that then opens the door for a larger nuclear strike involving more conventional (but still nuclear-armed) ICBMs. Kyle Mizokami, Popular Mechanics, "Russia Tests Yet Another Hypersonic Weapon," 27 Dec. 2018 With little discussion, the Lake Station City Council dealt a knockout blow Thursday to plans to build a food waste recycling plant on the northwest side of the city. Carole Carlson, Post-Tribune, "Lake Station council nixes food waste recycling project," 29 June 2018 So often a match like the 2008 Wimbledon Final serves as a knockout blow. Jon Wertheim, SI.com, "Mailbag: Grass Court Season, Equal Pay and the Fed-Rafa Documentary," 20 June 2018 The knockout blow didn’t come from a bomb but from a base hit by Lucas Duda in the sixth. Blair Kerkhoff, kansascity, "Alex Gordon stays hot as Royals get rare series-opening victory over Tigers | The Kansas City Star," 3 May 2018 Then, in a dizzying flourish of unthinkable events, Virginia came off the mat and delivered a knockout blow, stunning Louisville, 67-66. Jeff Greer, The Courier-Journal, "Mental errors destroyed the Cards in an ugly loss to Virginia. But there’s no time to dwell," 2 Mar. 2018 In one, Kirsty Hume wears a comfy sweater that oozes off her shoulder; in the other, a simple T-shirt dress that wondrously transformed, with two inner ties, into a draped knockout à la Isadora Duncan. Brooke Bobb, Vogue, "Tom Ford’s Gucci and 1980s BodyMap: These Are the 16 Collections We’d Like to See Reissued Now," 27 Dec. 2018 What Lesnar witnessed was Cormier, already the light heavyweight title holder, become a simultaneous two-division champion with a first-round knockout of Miocic. Simon Samano, USA TODAY, "Brock Lesnar returning to UFC, will fight new heavyweight champion Daniel Cormier," 8 July 2018 Hours earlier, despite predictions of a much closer race, Mr Erdogan and his party, plus their ultranationalist allies, scored a double knockout in Turkey’s elections. The Economist, "Erdogan inaugurates a new political era in Turkey," 28 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'knockout.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of knockout

Noun

1887, in the meaning defined at sense 1a

Adjective

1818, in the meaning defined at sense 1

Verb

1856, in the meaning defined at sense 1

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Statistics for knockout

Last Updated

3 Feb 2019

Look-up Popularity

Time Traveler for knockout

The first known use of knockout was in 1818

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More Definitions for knockout

knockout

noun

English Language Learners Definition of knockout

 (Entry 1 of 2)

: an occurrence in which a boxing match ends when a fighter has been knocked down by a punch and is unable to start fighting again before 10 seconds have passed
informal : a very attractive or appealing person or thing

knockout

adjective

English Language Learners Definition of knockout (Entry 2 of 2)

: causing someone to become unconscious
informal : extremely attractive or appealing
British, of a contest or competition : designed so that winning teams or players continue to play and losing teams or players do not

knockout

adjective
knock·​out | \ ˈnäk-ˌau̇t \

Medical Definition of knockout

: having all or part of a gene eliminated or inactivated by genetic engineering knockout mice predisposed to diabetes mellitus serve as animal models in the study of human diabetes

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Comments on knockout

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