Any of three species of black-and-white seabirds (genus Cepphus, family Alcidae). Guillemots have a pointed, black bill and red legs. Guillemots are deep divers that feed at the bottom. The best-known species, the black guillemot, breeds around the Arctic Circle and winters south to the British Isles, Maine, and the Bering Strait; it is about 14 in. (35 cm) long. The similar pigeon guillemot breeds along both coasts of the North Pacific, south to Japan and southern California; the spectacled guillemot breeds from Japan to the Kuril Islands. In British usage, the name also refers to birds called murres in the U.S.