noun co·hort \ˈkō-ˌhȯrt\

Definition of cohort

  1. 1a :  one of 10 divisions of an ancient Roman legionb :  a group of warriors or soldiersc :  band, group a cohort of supportersd :  a group of individuals having a statistical factor (as age or class membership) in common in a demographic study a cohort of premedical students the cohort of people born in the 1980s

  2. 2 :  companion, colleague a few of their … cohorts decided to form a company — Burt Hochberg

cohort was our Word of the Day on 02/02/2008. Hear the podcast!

Examples of cohort in a sentence

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

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

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 via French 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, and later to a single companion. Some usage commentators 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.

Origin and Etymology of cohort

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

First Known Use: 15th century

COHORT Defined for English Language Learners


noun co·hort \ˈkō-ˌhȯrt\

Definition of cohort for English Language Learners

  • : a friend or companion

  • : a group of people used in a study who have something (such as age or social class) in common

Medical Dictionary


noun co·hort \ˈkō-ˌhȯ(ə)rt\

Medical Definition of cohort

  1. :  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

Seen and Heard

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a rounded knoll or a ridge of ice

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