crupper

American  

[kruhp-er, kroop-] / ˈkrʌp ər, ˈkrʊp- /

noun

1. a leather strap fastened to the saddle of a harness and looping under the tail of a horse to prevent the harness from slipping forward.

2. the rump or buttocks of a horse.

3. armor for the rump of a horse.

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crupper British  

/ ˈkrʌpə /

noun

1. a strap from the back of a saddle that passes under the horse's tail to prevent the saddle from slipping forwards

2. the part of the horse's rump behind the saddle

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Etymology

Origin of crupper

1250–1300; Middle English cro ( u ) per, variant of cruper < Anglo-French. See croup ², -er ²