in Roman mythology, a woodpecker sacred to the god Mars. It was widely worshipped in ancient Italy and developed into a minor god. Picus was an agricultural deity associated particularly with the fertilization of the soil with manure. The woodpecker was also an important bird in augury.

Later rationalizations made Picus an early king of Italy. The Roman poet Virgil's Aeneid, Book VII, for instance, made him son of Saturn, father of Faunus, and grandfather of Latinus. In Ovid's Metamorphoses, Book XIV, the witch Circe turns Picus into a woodpecker when he refuses to be disloyal to his wife, Canens. As son of Saturn he later came to be identified with Zeus. His earliest representations were as a wooden pillar mounted with the image of a woodpecker. In more sophisticated form, Picus is a youth carved of marble with a woodpecker on his head. In zoology, Picus is a genus of woodpecker.