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Synonyms

knockout

American  
[nok-aut] / ˈnɒkˌaʊt /

noun

  • knockouts
    plural
  1. an act or instance of knocking out.

  2. the state or fact of being knocked out.

  3. a knockout blow.

  4. Informal. a person or thing overwhelmingly attractive, appealing, or successful.

  5. a panel in a casing, can, or box, especially of metal or plastic, so designed that it can readily be removed, as by punching, hammering, or cutting, to provide an opening into the interior.

    a knockout in a junction box.

  6. Machinery. a device for knocking something loose, as finished work from a lathe chuck.


adjective

  1. that knocks out.

    the knockout punch.

knockout British  
/ ˈnɒkˌaʊt /

noun

  1. the act of rendering unconscious

  2. a blow that renders an opponent unconscious

    1. a competition in which competitors are eliminated progressively

    2. ( as modifier )

      a knockout contest

  3. a series of absurd invented games, esp obstacle races, involving physical effort or skill

  4. informal a person or thing that is overwhelmingly impressive or attractive

    she's a knockout

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. to render unconscious, esp by a blow

  2. boxing to defeat (an opponent) by a knockout

  3. to destroy, damage, or injure badly

  4. to eliminate, esp in a knockout competition

  5. informal to overwhelm or amaze, esp with admiration or favourable reaction

    I was knocked out by that new song

  6. to remove the ashes from (one's pipe) by tapping

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms


Etymology

Origin of knockout

1810–20; 1935–40 knockout for def. 4; noun, adj. use of verb phrase knock out


Explanation

In the sport of boxing, a knockout is a blow that sends one of the boxers to the mat, unable to continue fighting. If you are down and can't rise before the ref counts to ten, consider it a knockout. In full-contact fighting sports, including boxing, karate, and kickboxing, the ultimate goal is a match-winning knockout of the opponent. Not all boxing matches end this way, but a knockout is the most exciting (and dangerous) way for a match to end. This word is also used to mean "gorgeous person," so if someone tells you you're a knockout, you can be sure they mean it as a compliment.

Keep Reading on Vocabulary.com

Vocabulary lists containing knockout

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Over the past two seasons, Premier League clubs have played 21 knockout ties against European opposition in the Conference League and Europa League - and won all 21.

From BBC ● Oct. 22, 2026

They do a knockout version of “Silver Threads and Golden Needles.”

From The Wall Street Journal ● Oct. 22, 2026

Fans of the game have long celebrated its full-bore regular season, when an October contest can be a de facto knockout.

From The Wall Street Journal ● Oct. 18, 2026

"I'm going to be the difference. I am going to back Fabio Wardley by knockout within six rounds. Yep, I said. I'm going for Fab within six."

From BBC ● Oct. 17, 2026

She was wearing this knockout tennis suit, and here I was in my black jeans and army jacket.

From "Burning Blue" by Paul Griffin

With 41 knockouts between them from 43 victories, few expect the contest to go the distance.

From BBC ● Oct. 16, 2026

Since fighting his first professional match in 2020, Vargas Jr. himself has built a steady record in the ring with 15 knockouts in 17 wins.

From Los Angeles Times ● Sep. 12, 2026

Additionally, England and France were put in opposite sides of the knockouts and on a path to meet either Spain or Argentina in the semi-finals if they all progressed.

From BBC ● Jul. 12, 2026

In the knockouts, some of the European nations have also impressed when dealing with adversity.

From BBC ● Jul. 8, 2026

Grandma hugged Zed and then Zed hugged Joey, and bam, faster than one of Joey’s knockouts, Zed had weaseled himself into becoming part of Joey’s family.

From "Lawn Boy Returns" by Gary Paulsen

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