a sheep, Ovis canadensis, found in the western mountains.
See also: bighorn sheep
- 1824  (1955)  The Mountain sheep & Goats often take the best windings to reach the Summits of the Mountains, but [are] often eccentric & choose entricacies not to be followed by man.
- 1965  . . . there was one 12-mile road snaking . . . down into a wilderness valley, frequented by mountain sheep and cougars and black bear, only to peter out into nothing.