Pronunciation: (big'hôrn"),[key] —n., —pl.-horns,(esp. collectively)-horn. a wild sheep, Ovis canadensis, of the Rocky Mountains, with large, curving horns. Also called cimarron, Rocky Mountain bighorn, Rocky Mountain sheep.
Pronunciation: (big'hôrn"),[key] —n. a river flowing from central Wyoming to the Yellowstone River in S Montana. 336 mi. (540 km) long.