CRUPPER, noun [See Croup.] 1. In the manege, the buttocks of a horse; the rump. 2. A strap of leather which is buckled to a saddle, and passing under a horses tail, prevents the saddle from being cast forward onto the horses neck. CRUPPER, verb transitive To put a crupper on; as, to crupper a horse.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI