Origin: 1475–85; < Middle Frenchcohorte < Latincohort- (stem of cohors) farmyard, armed force (orig. from a particular place or camp), cohort, retinue, equivalent to co-co- + hort- (akin to hortus garden); replacing late Middle Englishcohors < L nominative singular
Usage note A cohort was originally one of the ten divisions of a legion in the Roman army, containing from 300 to 600 men. The most common use of cohort today is in the sense “group” or “company”: A cohort of hangers-on followed the singer down the corridor. In a development emphasizing the idea of companionship, cohort has also come to mean a single companion, associate, or the like: The senator strode into the room followed by his faithful cohort, his son-in-law.
1422, from L. cohortem, acc. of cohors "enclosure," meaning extended to "infantry company" in Roman army (a tenth part of a legion) through notion of "enclosed group, retinue," from com- "with" + root akin to hortus "garden," from PIE *ghr-ti-, from base *gher- "to grasp, enclose" (see
yard (1)). Sense of "accomplice" is first recorded 1952, Amer.Eng.