cohort

noun

co·​hort ˈkō-ˌhȯrt 

1

: companion, colleague

… a few of their … cohorts decided to form a company …

—Burt Hochberg

2

a

: band, group

a cohort of supporters

b

: a group of individuals having a statistical factor (such as age or class membership) in common in a demographic study

a cohort of premedical students

the cohort of people born in the 1980s

c

: one of 10 divisions of an ancient Roman legion

d

: a group of warriors or soldiers

Did you know?

In ancient times, a cohort was a military unit, one of ten divisions in a Roman legion. The term passed into English in the 15th century, when it was used in translations and writings about Roman history. Once cohort became established in our language, its meaning was extended, first to refer to any body of troops, then to any group of individuals with something in common (as in “a cohort of law students” or “a cohort of people who were born in the same year”), and later to a single companion. Some writers on usage have objected to this last sense because it can be hard to tell whether the plural refers to different individuals or different groups. The “companion” sense is well established in standard use, however, and its meaning is clear enough in such sentences as “her cohorts came along with her to the game.”

Synonyms of cohort

• associate
• colleague
• peer
• fellow
• friend
• buddy
• classmate
• accomplice

Examples of cohort in a Sentence

The police arrested the gang's leader and his cohorts.

Depression was a common problem for people in that age cohort.

Recent Examples on the Web

In future windows, a younger, faster centre-back feels required to augment an ageing cohort, with Burn and Fabian Schar both 34 and only Malick Thiaw possessing much pace. — Chris Waugh, New York Times, 3 Sep. 2026

Only 13% of current billionaires are women—but as men over the age of 60 dominate the ultra-rich cohort, more than 1,235 female spouses (representing 90% of billionaire partners) will inherit a sizable chunk in the next decade. — Emma Burleigh, Fortune, 3 Sep. 2026

The inaugural cohort of the fellowship includes Reina Mun, Alice Bucknell, Alfredo Salazar-Caro and Auriea Harvey. — News Desk, Artforum, 2 Sep. 2026

In the finale, Alice confronts Easton at his home and has to acknowledge that an entire cohort of people — cops, other wealthy men, even Easton’s own daughter — were complicit in his crimes. — Ct Jones, Rolling Stone, 2 Sep. 2026

Word History

Etymology

Middle English, from Latin cohort-, cohors — more at court

First Known Use

15th century, in the meaning defined at sense 2c

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Kids Definition

cohort

noun

co·​hort ˈkō-ˌhȯrt 

1

a

: one of 10 divisions of an ancient Roman legion

b

: a group of warriors or followers

2

: companion sense 1, accomplice

Medical Definition

cohort

noun

co·​hort ˈkō-ˌhȯ(ə)rt 

: a group of individuals having a statistical factor (as age or risk) in common

the population consisted of two cohorts: 204 clearly exposed and 163 not exposed

—R. R. Suskind et al.