Breed of dog, originating as a cross between a terrier and a bulldog. Very powerfully built, it grows to about 40 cm/16 in tall, and has a short, usually white, coat, narrow eyes, and distinctive egg-shaped head. It was formerly used in bull-baiting. Pit bull terriers are used in illegal dog fights. The Staffordshire bull terrier is a distinct breed.Short-haired terrier originated in England by crossing the bulldog with terriers; SYN. bull terrier. bull-terrier, bull terrier.