1. (noun)Bighorn, Bighorn River a river that flows from central Wyoming to the Yellowstone River in southern Montana Synonyms: bighornsheep, cimarron
2. (noun)bighorn, bighorn sheep, cimarron, Rocky Mountain bighorn, Rocky Mountain sheep, Ovis canadensis wild sheep of mountainous regions of western North America having massive curled horns Synonyms: bighornsheep, cimarron, bighorn