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90s Slang You Should Know


or K.O. k.o. kayo

[noun key-oh, key-oh; verb key-oh] /noun ˈkeɪˈoʊ, ˈkeɪˌoʊ; verb ˈkeɪˈoʊ/ Slang.
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.
Origin of KO
First recorded in 1920-25; initial letters of knock out Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2017.
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Examples from the Web for KO
Contemporary Examples
Historical Examples
  • The scientist had been caught in the Singapore hotel room by KO and company, but had fought his way clear.

    The Caves of Fear John Blaine
  • KO is one of the Burmese equivalents of Mr., more respectful than Maung.

    A Civil Servant in Burma Herbert Thirkel White
  • KO and the stranger talked together for a moment, then the latter gestured toward the Tibetans.

    The Caves of Fear John Blaine
  • In a moment they were looking through what was evidently KO's entire luggage.

    The Caves of Fear John Blaine
  • The KO′-mĭs is built along all Bontoc war trails, though no others are known having the “anito” heads.

    The Bontoc Igorot Albert Ernest Jenks
  • If the slender man wasn't Long Shadow, at least he would have KO to deal with.

    The Caves of Fear John Blaine
  • MosKOe (mos'KO), Probably Poe had in mind the Mos'kenaso island.

British Dictionary definitions for KO


verb KO's, KO'ing, KO'd, k.o.'s, k.o.'ing, k.o.'d
a slang term for knock out See knockout
noun (pl) KO's, 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
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Slang definitions & phrases for KO



: aKO punch


A knockout; kayo (1922+ Prizefight)


: He KOed six in a row

Related Terms


The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D.
Copyright (C) 2007 by HarperCollins Publishers.
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