miniature bull terrier, breed of small, muscular dog developed in England in the early 19th cent. It stands up to 14 in. (35.6 cm) high at the shoulder and weighs about 17 lb (7.7 kg). Its short, flat, harsh coat is glossy white or white with brindle patches. As the bull terrier was being created from the bulldog and the white English terrier, dogs were produced in a wide variety of sizes. The toys, weighing from 4 to 7 lb (1.8-3.2 kg), were selectively bred and exhibited until about 1914, when interest in them waned. The medium-sized or miniature bull terriers have retained their popularity to this day and have continued to be bred to resemble in every detail the standard-sized bull terriers. The miniature is shown in the miscellaneous class at dog shows sanctioned by the American Kennel Club. See dog.

bull terrier, breed of large, muscular terrier originating in England around 1835. It stands from 19 to 22 in. (48.3-55.9 cm) high at the shoulder and weighs from 30 to 36 lb (13.6-16.3 kg). Its short, flat-lying, harsh coat is glossy white or, in the colored variety, most popularly brindle with white markings. Developed for dogfighting from a cross of bulldog and a now extinct English terrier, the bull terrier was renowned for its courage, strength, and intelligence. However, down through the years English breeders placed increasing emphasis on the breed's overall disposition and less on its aggressiveness. As a result, the bull terrier of today is a friendly, gentle dog that makes a responsible and devoted companion. See dog.

or Staffordshire terrier

Dog breed developed in 19th-century Britain for fighting other dogs in pits. It was created by crossing the bulldog (which at the time was longer-legged and more agile) with a terrier, possibly the fox terrier. Once known by such names as bull-and-terrier and half-and-half, the pit bull is a stocky, muscular, unusually strong dog with powerful jaws, standing 17–19 in. (43–48 cm) tall and weighing 30–50 lb (14–23 kg). Its stiff, short coat may be any colour, solid or variegated. Seealso bull terrier.

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Breed of dog developed in 19th-century England from the bulldog and the now-extinct white English terrier. The Spanish pointer was later bred into the line to increase its size. The bull terrier was developed as a courageous fighting dog but not an aggressive fight provoker, and it is generally friendly. A muscular dog, it is considered, for its weight, the strongest of all dogs. It has a short coat, tapering tail, erect ears, and deep-set eyes. It stands 19–22 in. (48–56 cm) high and weighs 50–60 lbs (23–27 kg). There are two varieties, coloured and white.

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