In Greek mythology and Roman mythology, a harpy (plural 'harpies') was a half-human and half-bird personification of storm winds, in Homeric poems.

They were generally depicted as birds with the heads of maidens, faces pale with hunger and long claws on their hands. Roman and Byzantine writers detailed their ugliness. Pottery art depicting the harpies featured beautiful women with wings. Ovid described them as human-vultures. The harpies seem originally to have been wind spirits (personifications of the destructive nature of wind).

Their name means "snatchers" or "swift robbers" and they steal food from their victims while they are eating and carry evildoers (especially those who have killed their family) to the Erinyes. When a person suddenly disappeared from the earth, it was said that he had been carried off by the harpies. Thus, they carried off the daughters of king Pandareus and gave them as servants to the Erinyes. In this form they were agents of punishment who abducted people and tortured them on their way to Tartarus. They were vicious, cruel and violent.

The harpies were called "the hounds of mighty Zeus" thus "ministers of the Thunderer (Zeus)". Later writers listed the harpies among the guardians of the underworld among other monstrosities including the Centaurs, Scylla, Briareus, Lernaean Hydra, Chimera, Gorgons and Geryon. Their abode is either the islands called Strophades, a place at the entrance of Orcus, or a cave in Crete.

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