Guillemot \Guil"le*mot`\, n. [F.] (Zo["o]l.) One of several northern sea birds, allied to the auks. They have short legs, placed far back, and are expert divers and swimmers. Note: The common guillemots, or murres, belong to the genus {Uria} (as {U. troile}); the black or foolish guillemot ({Cepphus grylle}, formerly {Uria grylle}), is called also {sea pigeon} and {eligny}. See {Murre}.