In Greek mythology,

Medusa (??d??sa "guardian, protectress"), also called Gorgo, was one of the three monstrous Gorgons. They were generally described as winged human females with living venomous snakes in place of hair. Those who gazed into her eyes would turn to stone. Medusa was beheaded by the Greek hero Perseus, who then used her head, which retained its ability to turn onlookers to stone, as a weapon until he gave it to the goddess Athena to place on her shield. In classical antiquity, the image of the head of Medusa appeared in the evil-averting device known as the Gorgoneion. Medusa and especially the Gorgoneion have been used since ancient times as a protection and abominable symbol and often as an antefix in temples and houses but also as decoration on armor, weapons, shields, chariots and various objects.

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