(n.) An arctic cetacean (Monodon monocerous), about twenty feet long. 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. Sometimes two horns are developed, side by side.

Loch Ness monster alevin baleen whale beluga benthon benthos blackfish blue whale cachalot dolphin finback fingerling fish fry game fish grilse humpback killer killer whale kipper man-eater man-eating shark marine animal minnow minny narwhal nekton panfish plankton porpoise salmon sea monster sea pig sea serpent sea snake shark smolt sperm whale sponge sulfur-bottom whale tropical fish whale