breed of terrier (dog) developed in the border country of England and Scotland to hunt and kill foxes that were preying on livestock. The border terrier stands about 13 inches (33 cm) and weighs 11 to 15 pounds (5 to 7 kg). It has a short, otterlike head, narrow shoulders, and a dense, weather-resistant coat of blue-gray and tan or golden or reddish brown. See dog for a list of selected breeds of terriers.