Scottish deerhound, breed of tall hound developed in Scotland in the 16th and 17th cent. It stands from 28 to 32 in. (71.1-81.3 cm) high at the shoulder and weighs from 75 to 110 lb (34.0-49.9 kg). Its medium-length coat is harsh and wiry and may be colored blue gray, brindle, red, or fawn, sometimes with white markings on the toes and chest. The deerhound was originally owned and bred exclusively by the aristocracy, who perfected its scenting ability and its combined speed and strength for hunting and bringing down deer. Today it is most commonly raised as a companion dog. See dog.