a bird’s horny projecting jaws; a bill:a parent bird with a caterpillar in its beak
the horny projecting jaw of animals other than birds, for example a turtle or squid.
informal a person’s nose:she can’t wait to stick her beak in
a projection at the prow of an ancient warship, typically shaped to resemble the head of a bird or other animal, used to pierce the hulls of enemy ships.