airedale terrier (âr´dāl), breed of dog developed in England in the 19th cent. It is the largest of the terrier group, standing about 23 in. (58.4 cm) high at the shoulder and weighing from 40 to 50 lb (18.1–22.7 kg). Its dense, wiry, close-lying coat is a mixture of tan, black, and grizzle in color. Although little can be said with certainty of its history prior to 1850, authorities generally believe the airedale was produced from crosses of the extinct black-and-tan terrier and the otterhound. It has been used to hunt a variety of game, trained as a police dog and dispatch bearer in war, bred for show competition, and kept as a pet. See dog.