n.
or bill
Stiff, projecting oral structure of birds and turtles (both of which lack teeth) and certain other animals (e.g., cephalopod s and some insects, fishes, and mammals).
The term bill is preferred for the beak of a bird, composed of upper and lower jaws covered by a horny sheath of skin, with the nostrils on top, usually at the base. The shapes and sizes of bills are adapted for obtaining food, preening, building nests, and other functions; they range from the long, slim bill of nectar-sipping hummingbirds to the sturdy, curved, nut-cracking bill of parrots.