Synonyms for Bighorn (same or very similar meaning)
WordNet sense 1 (a river that flows from central Wyoming to the Yellowstone River in southern Montana):
Bighorn RiverWordNet sense 2 (wild sheep of mountainous regions of western North America having massive curled horns):
cimarron, bighorn sheep, Ovis canadensis, Rocky Mountain bighorn, Rocky Mountain sheepFrom the ODE community, based on WordNetadd/edit