A native pony in the Western country.
1857. Davis and Monnastes advertise that they can do all manner of wrought and cast work, from a Steam Engine and Boiler down to Shoeing a Cultus Cayuse Horse.Oregon Weekly Times, January.
1869. The native horses become singularly skilled in bucking, and there are few riders who can keep the saddle or make them yield to the lines when they resort to their favorite amusement. Twice our kiyuse broke nearly out of the harness . The kiyuse is never perfectly tamed . The Western man always rides at a lope, and sometimes at a gallop, and when his pony is worn down he is turned out to grass, and a fresh one brought in, who usually bucks vigorously when he is called into service.A. K. McClure, Rocky Mountains, p. 302.
1909. You will go on horse back, provided the sure-footed little cayuse doesnt object, and refrains from bucking you off.N.Y. Ev. Post, Feb. 18.