n. A goat antelope (Oreamnos americanus) of the northwest North American mountains, having curved black horns and shaggy yellowish-white hair and beard. Also called Rocky Mountain goat. an animal with thick white fur which looks like a goat and lives in the western mountains of North America. or Rocky Mountain goat Ruminant (bovid species Oreamnos americanus) of the Yukon to the northern Rockies that is more closely related to antelopes than to goats. Stocky, with a hump at the withers, mountain goats stand about 40 in. (1 m) at the shoulder. Both sexes bear short, hollow, slightly backward-curving, black horns. The shaggy, coarse white hair covers a thick, woolly underfur, and a beard frames the slender muzzle. The hooves are black. Mountain goats are agile climbers and can leap more than 12 ft (3.5 m). They live in small bands above the timberline, eating moss, lichen, and scrub foliage