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Synonyms

KO

American  
[kay-oh, kay-oh, kay-oh] / ˈkeɪˈoʊ, ˈkeɪˌoʊ, ˈkeɪˈoʊ /
Or K.O.,

noun

  • KO's
    plural
  1. a knockout in boxing.


verb (used with object)

  • KO's,
    present (3rd person singular)
  • KO'd,
    past participle,  past
  • KO'ed,
    past participle,  past
  • KOed,
    past participle,  past
  • KO'ing,
    present participle
  • KOing
    present participle
  1. to knock unconscious, especially in a boxing match; knock out.

KO British  
/ ˈkeɪˈəʊ /

verb

  1. a slang term for knock out See 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

noun

  1. a slang term for 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

Other Word Forms

Inflected Forms

Nouns

Participles

Conjugated Forms

Present

Past

Future


Etymology

Origin of KO

First recorded in 1920–25; initial letters of knock out


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:

Coca-Cola KO -0.68%decrease; down pointing triangle is waging a high-stakes corporate battle with more than $20 billion at stake, and the opponent isn’t Pepsi or even Dr Pepper.

From The Wall Street Journal ● Jun. 21, 2026

During the past several years, Brush has suggested KO, UTZ and HSY in his stock newsletter, Brush Up on Stocks.

From MarketWatch ● Feb. 7, 2026

"We got Justin the good look and KO got the rebound and put it back."

From Barron's ● Nov. 12, 2025

American legend Marvin Hagler survived some vicious bouts, notably his 1985 war with Thomas Hearns, before retiring without a losing KO on his record.

From BBC ● May 8, 2024

And you never want Daddy to go for the KO.

From "The Hate U Give" by Angie Thomas

Put into the same boxing ring to duke it out, the movie’s unintentional silliness easily KO’s its blips of emotional gravity.

From Salon ● Nov. 8, 2025

According to the European Parliament report, Mr Brezja's mobile phone was hacked when he was KO's campaign manager during the 2019 parliamentary election.

From BBC ● Feb. 19, 2024

Animals services have identified who they believe was KO’s owner using the dog’s microchip but have so far been unsuccessful in finding him.

From Los Angeles Times ● Jan. 4, 2023

The interiors — much like Studio KO’s other work — are lavish but not ostentatious, precise but not severe.

From New York Times ● Sep. 14, 2018

Its private villas, the core of Studio KO’s architectural practice, offer eloquent but plainspoken dialogues with their remote, sometimes forbidding settings.

From The Wall Street Journal ● Aug. 13, 2018

They’re watching because they want to see Brenda say the skeleton looks like Calista Flockhart, or Cindy get KO’d by a black cat.

From Salon ● Jun. 11, 2026

Onegame after he was unstoppable, A.D. was KO’d, swarmed into submission, held to five baskets with four turnovers, 11 points after taking 11 shots, illustrating the Warriors’ best chance to win this series.

From Los Angeles Times ● May 5, 2023

That’s right, Adesanya, the UFC 185-pound champion, has never been KO’d by Pereira inside the octagon and the fighter better known as “The Last Stylebender” has only lost once in his MMA career.

From Washington Times ● Nov. 11, 2022

When 58-year-old Evander Holyfield was KO’d a little over a year ago in a boxing match in Hollywood, Fla., the Florida State Boxing Commission medically suspended him from fighting in the state for 30 days.

From Washington Post ● Oct. 7, 2022

"Oh, sure, man, that's all right. You got KO'd, right? Can't win 'em all."

From "The Contender" by Robert Lipsyte

Four quarters continue to be out of the question, which WSU proved again on a toasty Saturday afternoon on the Palouse, getting KO'ed 50-16 by Southern California in the Pac-10 opener for both teams.

From Seattle Times ● Sep. 26, 2010

The rest of the sports news was much more routine, as long as you’ve gotten used to a major sport KO’ing itself with a mismanaged lockout.

From New York Times ● Nov. 16, 2011

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