Definition of narwhal in English English dictionary
An Arctic cetacean, about 20 feet long; the male has a single twisted pointed canine tooth or tusk projecting forward like a horn
The male usually has one long, twisted, pointed canine tooth, or tusk projecting forward from the upper jaw like a horn, whence it is called also sea unicorn, unicorn fish, and unicorn whale
or narwal or narwhale Toothed whale (Monodon monoceros, family Monodontidae) of the Arctic, found in groups of 15-20 along coasts and sometimes in rivers. Narwhals are mottled gray, attain a length of 11.5-16 ft (3.5-5 m), and have no dorsal fin. They have only two teeth, at the upper jaw tip. The male's left tooth is a straight, protruding tusk, up to 8.9 ft (2.7 m) long, that is grooved on the surface in a left-handed spiral. It was prized in medieval times as the unicorn horn. The tusk is thought to have evolved as a sexual display. Narwhals eat fishes, cephalopods, and crustaceans. They are hunted by humans for their tusks and meat