Polycephaly is the condition of having more than one head. The term is derived from the Greek stems poly- (Greek: "πολύ") meaning "multiple" and kephalē- (Greek: "κεφάλη") meaning "head". A polycephalic organism may be thought of as one being with a supernumerary body part, or as two or more beings with a shared body.

Polycephaly is the condition of having more than one head. The term is derived from the Greek stems poly- (Greek: "πολύ") meaning "multiple" and kephalē- (Greek: "κεφάλη") meaning "head". A polycephalic organism may be thought of as one being with a supernumerary body part, or as two or more beings with a shared body.