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.