The beak, bill, or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young. The terms beak and rostrum are also used to refer to a similar mouthpart in some Ornithischian dinosaurs, monotremes, cephalopods (see Cephalopod beak), cetaceans, billfishes, pufferfishes, turtles, Anuran tadpoles and sirens.

Beak (stylized as BEAK>) is a UK based band, consisting of Geoff Barrow (of Portishead) with Billy Fuller (Robert Plant) and Matt Williams (MXLX, Fairhorns).