KO

verb

KO'd kā-ˈōd How to pronounce KO (audio)
ˈkā-(ˌ)ōd
; KO'ing kā-ˈō-iŋ How to pronounce KO (audio)
ˈkā-(ˌ)ō-iŋ
Synonyms of KOnext

transitive verb

: to knock out (as in boxing)

Examples of KO in a Sentence

He was KO'd in the second round.

Word History

First Known Use

1926, in the meaning defined above

Time Traveler
The first known use of KO was in 1926

Browse Nearby Words

Cite this Entry

“KO.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/KO. Accessed 9 Jun. 2026.

Kids Definition

KO

1 of 2 noun
(ˈ)kā-ˈō How to pronounce KO (audio)
ˈkā-ō
plural KO's
: a knockout in boxing

KO

2 of 2 verb
KO'd kā-ˈōd How to pronounce KO (audio)
ˈkā-ōd
; KO'ing -ˈō-iŋ How to pronounce KO (audio)
-ō-
: to knock out in boxing

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