In Greek mythology, a gorgon is an evil woman creature having her hair made of living and venomous snakes. Legend says that looking at the face of a gorgon will turn a person into stone. Derived from the Greek word for "dreadful", the term most commonly refers to any of three wicked sisters, Medusa, Stheno and Euryale, who were daughters of Phorcys and Ceto. Among the three sisters, Medusa was the best known and was the only mortal. She was ultimately killed by Perseus who cut off her head while he looked at her reflection in his shield.

Besides having hair of living snakes, the gorgons were covered with impenetrable scales, with hands made of brass, sharp fangs and a beard. They lived in the ultimate west, near the ocean, and guarded the entrance to the underworld.

Image and sculptures of gorgons are often used by the Greeks to ward off the dark forces of evil. Many of such works were found on temples and graves, as well as on the shields of soldiers. Gorgon heads or gorgoneions were also found on the older coins of Athens. Gorgons, especially Medusa, have become a common symbol in Western culture, appearing in art, literature, and elsewhere throughout history.