COHORT (

See also:

• LAT

Lat. cohors)  , originally a place enclosed: in the Roman army, the name of a unit of infantry . The troops of the first grade, the legions, were divided into cohorts, of which there were ten in each legion: the cohort thus contained 600 men . Among the troops of the second grade (the auxilia) the cohorts were independent foot regiments 500 or loon strong, corresponding to the alae, which were similar regiments of cavalry; they were generally posted on the frontiers of the Empire in small forts of four to eight acres, each holding one cohort or ala . The special troops of Rome itself, the Praetorian Guard, the Urbanae Cohortes, and the Vigiles (fire brigade), were divided into cohorts (see further ROMAN ARMY) . The phrase cohors praetoria or cohors amicorum was sometimes used, especially during the Roman republic, to denote the suite of the governor of a province; hence developed the Praetorian cohorts which formed the emperor's bodyguard . In biology, " cohort " is a term for a group of allied orders or families of plants or animals .