knockout

noun
knock·​out | \ ˈnäk-ˌau̇t How to pronounce knockout (audio) \

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
knocked out; knocking out; knocks out

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

Perhaps more importantly, Croatia went to extra-time in all three of its knockout-round games, including penalty shootouts against Denmark and Russia. Martin Rogers, USA TODAY, "How the World Cup final between France and Croatia will be won," 13 July 2018 Brazil got second-half goals from Neymar and Roberto Firmino to hand Mexico a loss in the first game of the knockout round for a seventh consecutive World Cup. Kevin Baxter, latimes.com, "Brazil and Neymar eliminate Mexico from World Cup with a 2-0 victory," 2 July 2018 Like Messi, Ronaldo has never scored in a knockout round match at the World Cup. Tim Booth, BostonGlobe.com, "Cristiano Ronaldo and Portugal ousted by Uruguay," 30 June 2018 The World Cup knockout rounds will begin Saturday and there is a chance Mexico and Portugal could meet, but only in the semi finals. Kathleen Joyce, Fox News, "World Cup fans speculating about 'Simpsons' soccer episode," 28 June 2018 Victory over South Korea would've comfortably seen the world champions through to the knockout rounds. Nathan Hilditch, Pro Soccer USA, "South Korea 2-0 Germany: Champions curse strikes again as Germany exits World Cup," 27 June 2018 Mexico, Sweden and Germany all have a chance to advance to the knockout rounds, and every position in the group will be up for grabs on June 27th. Nick Schwartz, For The Win, "The best- and worst-case scenarios for Mexico and Germany in Group F," 24 June 2018 Russians will enjoy the sight of their national team in the knockout round (but not for much longer). Cincinnati.com, "Enquirer soccer writers predict 2018 FIFA World Cup winner," 16 June 2018 Post-makeup, her knockout punch for keeping it locked in all night is Cinema Secrets Super Sealer Mattifying Setting Spray. Jamie Beckman, Allure, "Backstage Beauty Secrets From the Cast and Crew of Hamilton and Sleep No More," 13 Aug. 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

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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 How to pronounce knockout (audio) \

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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