Polycephaly

Polycephaly is a condition of having more than one head. The term is derived from the Greek stems poly- (Greek: "πολύ") meaning 'much' and kephali- (Greek: "κεφάλι") meaning "head", and encompasses bicephaly and dicephaly (both referring to two-headedness). A variation is an animal born with two faces on a single head, a condition known as diprosopus. In medical terms these are all congenital cephalic disorders.