Staffordshire terrier, breed of strong, muscular terrier developed in England in the early 19th cent. It stands from 17 to 19 in. (43.1–48.3 cm) high at the shoulder and weighs from 35 to 50 lb (15.9–22.7 kg). Its short, close-lying, stiff coat is glossy and may be any color or combination of colors except solid white. As the popularity of bullbaiting and bearbaiting began to decline and the matching of dog against dog became more the fashion, British breeders crossed bulldogs with a now extinct black-and-tan terrier to produce the smaller, more agile pit dog necessary for this sort of contest. The result was the Staffordshire terrier. In recent times the Staffordshire has been raised as a pet and watchdog. See dog.