a. A group or band of people.
b. A companion or associate.
c. A generational group as defined in demographics, statistics, or market research: "The cohort of people aged 30 to 39 ... were more conservative" (American Demographics).
a. One of the 10 divisions of a Roman legion, consisting of 300 to 600 men.
b. A group of soldiers.
[Middle English, from Old French cohorte, from Latin cohors, cohort-; see gher-1 in the Appendix of Indo-European roots.]
Usage Note: The English word cohort comes from the Latin word cohors, which meant "an enclosed area" or "a pen or courtyard enclosing a group of cattle or poultry." By extension, the word could refer to any group in general and in particular to a company of soldiers or a troop of cavalry in the army of ancient Rome. The group of men forming the bodyguard of a Roman general or the retinue of a provincial governor was also called a cohors. Because of this history, some people insist that the English word cohort should be used to refer only to a group of people and never to an individual person. But the use of cohort in reference to individuals has become so common, especially in the plural, as to overshadow the use in the singular to refer to a group. Both in our 1988 and 1999 surveys, 71 percent of the Usage Panel accepted the sentence The cashiered dictator and his cohorts have all written their memoirs. These results stand in stark contrast to those of our 1965 survey, in which 69 percent rejected the usage. Moreover, the Panel is divided regarding the traditional usage referring to a group. In 1988, 43 percent accepted The gangster walked into the room surrounded by his cohort, and in 1999, 56 percent accepted Like many in her cohort, she was never interested in kids when she was young.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.