A grizzly is a large North American species of bear also known as a silvertip bear. When you go camping and hiking in the western United States, park rangers might teach you what to do if you see a grizzly.
The grizzly bear's formal Latin name, Ursus arctos horribilis, came from confusion between grizzly and grisly, or "horrible." Grizzly bears are known for being solitary and having brown fur tipped in white or gray. The adjective grizzly probably arose from these "grizzled" or gray-colored hairs, since it describes appearing aged or old, especially because of graying hair.