troop: [16] Troop was borrowed from French troupe (acquired again as troupe in the 19th century). This appears to have been a backformation from troupeau ‘flock, herd’, a diminutive formation based on Latin troppus. And troppus itself may have been of Germanic origin. By the time the word reached English it was already being applied to a ‘group of soldiers’, and its plural was being used as a collective term for ‘soldiers’. => troupe
troop (n.)
1540s, "body of soldiers," 1540s, from Middle French troupe, from Old French trope "band of people, company, troop, crowd" (13c.), of uncertain origin, perhaps from Frankish *throp "assembly, gathering of people" or another Germanic source, perhaps related to Old English ðorp, Old Norse thorp "village" (see thorp). OED derives the French word from Latin troppus "flock," which is of unknown origin but also might be from the proposed Germanic source. Of groups of animals from 1580s. Specifically as "a subdivision of a cavalry force" from 1580s; of Boy Scouts from 1908. Troops "armed forces" is from 1590s.
troop (v.)
1560s, "to assemble," from troop (n.). Meaning "to march" is recorded from 1590s; that of "to go in great numbers, to flock" is from c. 1600. Related: Trooped; trooping.
实用例句
1. I was assigned to Troop A of the 10th Cavalry.
我被派往第10骑兵队的A连。
来自柯林斯例句
2. There are reports of fresh troop movements across the border.
有报告说，新近有军队越过边境。
来自柯林斯例句
3. There were reports of troop movements.
有报道称将要调动军队。
来自柯林斯例句
4. The officer ordered the troop to retire from the action.
军官下令将部队撤出战斗.
来自《简明英汉词典》
5. Troop movements can be observed from space by a satellite.