In ancient Greece, the Gorgoneion was originally a horror-creating apotropaic pendant showing the Gorgon's head. It was worn by the Olympian deities Zeus and Athena as a protective pendant. It was also worn, among other godlike attributes, as a royal aegis by rulers of the Hellenistic age and later on the busts of Roman Emperors. In Greek mythology, the Gorgon was a terrifying female creature. The name derives from the Greek word gorgós, which means "dreadful." While descriptions of Gorgons vary across Greek literature, the term commonly refers to any of three sisters who had hair of living, venomous snakes, and a horrifying visage that turned those who beheld it to stone. Traditionally, while two of the Gorgons were immortal, Stheno and Euryale, their sister Medusa was not, and was slain by the mythical demigod and hero Perseus. Gorgons were a popular image of Greek mythology, appearing in the earliest of written records of Ancient Greek religious beliefs such as those of Homer. Because of their legendary gaze, images of the Gorgons were put upon objects and buildings for protection. For example, an image of a Gorgon holds the primary location at the pediment of the temple at Corfu. It is the oldest stone pediment in Greece and is dated to c. 600 BC.