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Synonyms

co-occur

American  
[koh-uh-kur] / ˌkoʊ əˈkɜr /
Or cooccur

verb (used without object)

co-occurred, co-occurring
  1. to appear together in sequence or simultaneously.


Other Word Forms


Etymology

Origin of co-occur

First recorded in 1950–55


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Other types could include conditions that can co-occur with autism, such as ADHD, depression and epilepsy.

From BBC ● Aug. 21, 2026

Previous studies have demonstrated that wildfires and extreme heat co-occur with great frequency, and that people’s physiological responses to the hazards are related, he said.

From Los Angeles Times ● Feb. 3, 2024

Red deer density is only reduced when wolves, lynx and bears co-occur at the same site.

From Science Daily ● Jan. 10, 2024

If you look at the way that choice occurs in common speech, both within the United States and in Ireland, it tends to co-occur with consumer things.

From Slate ● May 16, 2022

These so-called comorbidities—meaning the conditions co-occur with Internet addiction—include “attention-deficit hyperactivity, mood, anxiety and personality disorders.”

From "A Deadly Wandering: A Mystery, a Landmark Investigation, and the Astonishing Science of Attention in the Digital Age" by Matt Richtel

In every place, copies of the Borg co-occurred with DNA linked to a methane-oxidizing archaeon called Methanoperedens.

From Science Magazine ● Jul. 15, 2021

In the early 1980s, for instance, it was clinicians’ observations that pneumocystis pneumonia co-occurred with Kaposi’s sarcoma in men in San Francisco that led to the identification of HIV/AIDS as the common risk factor19.

From Nature ● Mar. 23, 2020

What happened in 2015 is that very low precipitation co-occurred with record high temperatures.

From National Geographic ● Sep. 14, 2015

A 2021 study of more than 42,000 caregivers of children ages 3 to 17 found that 78% of autistic children had at least one co-occurring psychiatric condition, compared with 14% of non-autistic kids.

From Los Angeles Times ● Nov. 20, 2025

Among the most common co-occurring illnesses were chronic fatigue syndrome and mast cell activation syndrome, or MCAS, a condition where patients experience intense episodes of diarrhea, hives, vomiting, and, in many cases, life-threatening anaphylaxis attacks.

From Slate ● Sep. 15, 2025

According to a report last year from The Pew Charitable Trusts, while 2% of the U.S. population has a co-occurring disorder, people with both diagnoses make up a disproportionate 15% of arrests.

From Seattle Times ● Mar. 12, 2024

Nevertheless, these results suggest that these co-occurring colour morphs may be an adaptive response to climate conditions.

From Science Daily ● Feb. 14, 2024

Duravsula added that "neurodivergent people who do not have co-occurring antagonistic personality styles will often be quite contrite and apologetic if they are informed that their conduct or words may have hurt someone."

From Salon ● Nov. 29, 2023

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