WordReference Random House Unabridged Dictionary of American English © 2025
cay•use 
(kī yo̅o̅s′, kī′o̅o̅s),USA pronunciation n. 
Cay•use (kī yo̅o̅s′, kī′o̅o̅s),USA pronunciation n., pl. -us•es, (esp. collectively) -use.
            - Dialect Terms[Western U.S.]a horse, esp. an Indian pony.
- Dialect TermsAlso called cayuse′ wind′. [Northwestern U.S.]a cold wind blowing from the east.
- named after the Cayuse 1830–40, American.
Cay•use (kī yo̅o̅s′, kī′o̅o̅s),USA pronunciation n., pl. -us•es, (esp. collectively) -use.
- Language Varietiesa member of a tribe of North American Indians now living in Oregon.