any of a family (Hydrobatidae) of petrels; esp., a black-and-white species (Hydrobates pelagicus) of the N Atlantic and the Mediterranean
See storm petrel in American Heritage Dictionary 4
noun
Any of various small sea birds of the family Hydrobatidae, especially Hydrobates pelagicus, of the North Atlantic and the Mediterranean, having sooty plumage and a white rump. Also called stormy petrel.