KO

or K.O., k.o., kay·o

[ noun key-oh, key-oh; verb key-oh ]

/ noun ˈkeɪˈoʊ, ˈkeɪˌoʊ; verb ˈkeɪˈoʊ /

Slang.

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See synonyms for KO on Thesaurus.com

noun, plural KO's.

a knockout in boxing.

verb (used with object), KO'd, KO'ing.

to knock unconscious, especially in a boxing match; knock out.

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“Was” is used for the indicative past tense of “to be,” and “were” is only used for the subjunctive past tense.

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Origin of KO

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

Words nearby KO

knurled, knurling, knurly, Knussen, Knut, KO, koa, koala, koan, koap, kob

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use KO in a sentence

“There should be a statue of John Carlos in every city,” KO opined.
Keith Olbermann Makes Hilarious Return to ESPN, But for How Long?|Lloyd Grove|August 27, 2013|DAILY BEAST
Ko Young-hui died of breast cancer in exile in Paris in 2004.
North Korea IDs Mystery Woman as Kim Jong-Un’s Wife—But Who Is She, Really?|Nate Thayer|July 26, 2012|DAILY BEAST
Ko is portrayed speaking in the film over still images of her nurturing Kim Jong-un.
North Korea IDs Mystery Woman as Kim Jong-Un’s Wife—But Who Is She, Really?|Nate Thayer|July 26, 2012|DAILY BEAST
“I think it is a significant turn in U.S. policy toward Myanmar [Burma],” Thein Sein adviser Ko Ko Hlaing crowed to Reuters.
Hillary Clinton in Burma: Why She's Visiting the Oppressed State|Lennox Samuels|November 19, 2011|DAILY BEAST

Kano's transient flowers were grown, for the most part in pots, and these his daughter Um-ko loved to tend.
The Dragon Painter|Mary McNeil Fenollosa
Um-ko and her father were well known at the temple, and worshipped often before its golden altars.
The Dragon Painter|Mary McNeil Fenollosa
Um-ko sat motionless against the silver fusuma, an ivory image, crowned and robed in shimmering gray.
The Dragon Painter|Mary McNeil Fenollosa
All at once it seemed to Um-ko an unbearable thing for any spark of life to be so prisoned.
The Dragon Painter|Mary McNeil Fenollosa
She went into her tiny chamber, and from her treasures brought out a metal mirror given her by the young wife, Uta-ko.
The Dragon Painter|Mary McNeil Fenollosa

British Dictionary definitions for KO

k.o.

/ (ˈkeɪˈəʊ) /

verb KO's, KO'ing, KO'd, k.o.'s, k.o.'ing or k.o.'d

a slang term for knock outSee knockout

noun plural KO's or k.o.'s

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