KO

1 of 2

noun

(ˌ)kā-ˈō How to pronounce KO (audio) ˈkā-(ˌ)ō How to pronounce KO (audio)
Synonyms of KOnext
: knockout entry 1

KO

2 of 2

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

transitive verb

: to knock out (as in boxing)

Examples of KO in a Sentence

Noun He scored a KO in the second round. Verb He was KO'd in the second round.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
In early 2025, Subway bid farewell to Coke (KO) in favor of its new beverage supplier, Pepsi (PEP). — Francisco Velasquez, Quartz, 3 Apr. 2025

Word History

Etymology

Noun

knock out

First Known Use

Noun

1911, in the meaning defined above

Verb

1926, in the meaning defined above

Time Traveler
The first known use of KO was in 1911

Rhymes for KO

See All Rhymes for KO

Browse Nearby Words

knysna boxwood
KO
koa
See all Nearby Words

Cite this Entry

“KO.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/KO. Accessed 11 Apr. 2025.

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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

More from Merriam-Webster on KO

Britannica.com: Encyclopedia article about KO

Last Updated: - Updated example sentences
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