Circe (SUR-see) is, in Greek mythology, daughter of Perse and the sun god Helios, and mother of Aega, the sun goddess. As an adult Circe lived on the island of Aeaea and amused herself by decoying sailors there to turn them into beasts. According to Homer's The Odyssey, she changed Odysseus' companions into swine by giving them a magic drink. However, Hermes came to Odysseus' aid, giving him a black root which would allow him to break her spell. Seeing that her magic was useless, she changed all Odysseus' men back to normal, and they lived with her for a year. As is so often the case in these stories, Odysseus and Circe have sex, and in some Greek legends (though not Homer's) she bore him several children; their youngest son Telegonus would eventually unknowingly kill his father and marry Penelope. Circe also had the hots once for the king Picus, who spurned her advances, in revenge for which she turned him into a woodpecker, to his wife Canen's despair: after Canen had searched for him for six days in vain, she threw herself into the Tiber river and evaporated.

Circe has the contradictory nature often attributed to women through the ages. She is an embodiment of "feminine" virtues: she nurtures, bathes, feeds, and clothes Odysseus and his men, and soothes and heals them. She can wield her charms over wild animals as well, enchanting ferocious lions and wolves. But she is also a powerful sorcerer who can use her powers for evil; her turning of men into animals is capricious and cruel. She has many of the attributes of a witch, being likened to a cat and portrayed as using a wand and cauldron to work her spells. She is a beautiful woman, perhaps even a nymph, with a "dire divine beauty", and men find her so desirable that she is impossible to resist. Thus A.Word.A.Day defines Circe as an eponym for "an irresistibly charming woman".

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