Irish water spaniel, breed of large sporting dog developed in Ireland in the 19th cent. The tallest of the spaniels, it stands about 23 in. (58.4 cm) high at the shoulder and weighs between 45 and 65 lb (20.4–29.5 kg). Its dense, liver-colored coat is tightly curled and water-repellent. The tapering, smooth-coated tail and the topknot of long, loose curls that hang from a peak between the eyes are characteristic of the breed. A natural water dog with great endurance, the Irish water spaniel is often used to retrieve ducks. However, its coat, which may snag in heavy underbrush, makes it less suitable for hunting upland game. See dog.