co-occur

verb

co-oc·​cur ˌkō-ə-ˈkər How to pronounce co-occur (audio)
co-occurred; co-occurring
Synonyms of co-occurnext

intransitive verb

: to occur at the same time or in the same place
symptoms that often co-occur
co-occurring species
… certain words co-occur or collocate regularly with certain other words.—Morton Benson
co-occurrence
ˌkō-ə-ˈkər-ən(t)s How to pronounce co-occur (audio)
noun
plural co-occurrences
co-occurrence of the reactions
co-occurrence of two diseases

Synonyms of co-occur

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Examples of co-occur in a Sentence

the chronic depression that so often co-occurs with drug abuse
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.
Diseases that tend to co-occur often present themselves consecutively. — Benjamin P. Brown, The Conversation, 7 Apr. 2026 In the world of language, there are certain trends in terms of words that frequently co-occur in phrases or sentences together, some-thing called collocation. — Literary Hub, 21 Apr. 2026 Per Mayo Clinic, these conditions often co-occur, increasing risks for heart attack, stroke, and organ damage. — Escher Walcott, PEOPLE, 27 Jan. 2026 It’s not known if Victoria Jones also had a co-occurring mental illness but the past year had become increasingly turbulent for her. — Martha Ross, Mercury News, 8 Jan. 2026 See All Example Sentences for co-occur

Word History

First Known Use

1957, in the meaning defined above

Time Traveler
The first known use of co-occur was in 1957

Rhymes for co-occur

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Browse Nearby Words

cooba
co-occur
co-occurrent
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Cite this Entry

“Co-occur.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/co-occur. Accessed 7 Jul. 2026.

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