A wolfhound is a very large dog of a kind that was originally bred to hunt wolves — tall, long-legged, and fast, with a rough shaggy coat in the best-known types. The word rarely stands alone; you almost always hear it with the breed name in front: an Irish wolfhound (the famous one, one of the tallest dog breeds in the world, standing as high as a person's waist or higher) or a Russian wolfhound (another name for the borzoi). Because real wolf hunting ended long ago, no wolfhound today does the job its name describes; they are kept as pets, and owners will tell you these giant dogs are unusually gentle and calm indoors, which surprises people. So the word carries a nice little contradiction: a frightening name on a soft-natured animal. In everyday English it mostly turns up when someone is describing a dog that is startlingly big, and it often appears in writing about history, castles, or old noble families, where wolfhounds were a sign of wealth.