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

The distance between $167,970 and $44,115 is the architecture of American inequality, expressed in retirement savings data—a small cohort of high-balance savers dragging the average skyward while the rest of the country lives in the median. —Nick Lichtenberg, Fortune, 17 June 2026

As a result, this demographic cohort has seen its financial cushions evaporate entirely. —Arthur Zaczkiewicz, Footwear News, 17 June 2026

For Ahn, ensuring that future means preserving and honoring the pipeline that shaped his own cohort. —Joshua Encinias, IndieWire, 17 June 2026

Their cohort’s graduation year of 2038 will also bring with it the school’s 400th anniversary, the second-oldest public institution for secondary education in our nation’s history, its foundation dating back to Connecticut’s colonial times in 1638. —Dr. Andraé Townsel, Hartford Courant, 16 June 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

Podcast

Get Word of the Day delivered to your inbox!

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.