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

On May 11 in Fairfax, Va., Barrios scored a spectacular second-round knockout of Juan Jose Velasco of Argentina with a vicious left hook to the liver. John Whisler, ExpressNews.com, "Mario Barrios hoping to join elite club of San Antonio champions," 14 Aug. 2019 Lauren Murphy of Anchorage scored a spectacular knockout in a triumphant return to the UFC octagon Saturday in Newark, New Jersey. Beth Bragg, Anchorage Daily News, "Anchorage’s Lauren Murphy uses her knee to knock out foe and return to UFC win column," 4 Aug. 2019 The fifth strikeout, the 2,397th of his career, was a three-pitch knockout and jumped him to third on his own. Los Angeles Times, "Clayton Kershaw tops Sandy Koufax in strikeouts, Will Smith hits grand slam in Dodgers’ win," 1 Aug. 2019 The family-style dessert platter with fruit, sorbets and cakes are a knockout. Michael Mayo, sun-sentinel.com, "8 picks for great meal deals during Fort Lauderdale restaurant months," 31 July 2019 With no state championships at Louisa County, Trice didn’t bring a knockout resume. Washington Post, "30 years later, Sheila Trice remembers holding NCAA record," 27 July 2019 Lawrence went 8-0 as an amateur, all eight of his fights ending in a submission or a knockout. Robert Rimpson, The Courier-Journal, "MMA fighter Lance 'The Tornado' Lawrence is one fight away from his UFC dream," 12 July 2019 With the win at Stade Oceane in Le Havre, France, the Americans completed Group F play undefeated and advanced to a round-of-16 knockout match against Spain on Monday. NBC News, "U.S. women beat Sweden at World Cup 2-0, complete group play undefeated," 20 June 2019 Cejudo defended his flyweight belt against former bantamweight champ T.J. Dillashaw with a first-round knockout in January. Patrick Rose, chicagotribune.com, "Tony Ferguson beats Donald Cerrone by TKO at UFC 238 at the United Center," 9 June 2019

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

18 Aug 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 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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