Beak

The beak or bill is an external rostrum structure found mostly in birds. A beak is used for pecking, grasping, and holding, preening, courtship, and feeding young. The terms beak and rostrum are also used to refer to a similar organ in some non-avian theropods, ornithischians, pterosaurs, cetaceans, dicynodonts, rhynchosaurs, anuran tadpoles, turtles, monotremes, sirens, pufferfish, billfishes, parrotfish and cephalopods.