Boston terrier, breed of small, lively nonsporting dog developed in the United States in the second half of the 19th cent. It stands between 14 and 17 in. (35.6–43.2 cm) high at the shoulder and weighs from 13 to 25 lb (5.9–11.3 kg). Its short, smooth, glossy coat may be brindle or black, both with white markings. One of the few breeds native to the United States, it was developed in Boston from a cross between the bulldog and a now extinct white English terrier. Since its perfection in the 1880s, the Boston terrier has steadily increased in popularity as a companion and house pet. See dog.