Cetus (mythology)

In Ancient Greek, the word kētos (κῆτος, plural kētē or kētea, κήτη or κήτεα)—Latinized as cetus (pl. cetea)—denotes a large fish, a whale, a shark, or a sea monster. The sea monsters slain by Perseus and Heracles were each referred to as a cetus by ancient sources. The term cetacean (for whale) originates from cetus. In Greek art, cetea were depicted as serpentine fish. The name of the mythological figure Ceto is derived from ketos. The name of the constellation Cetus also derives from this word.

When Queen Cassiopeia boasted that her daughter Andromeda was more beautiful than the Nereids, this invoked the wrath of Poseidon who sent the sea monster Cetus to attack Æthiopia. Upon consulting a wise oracle, King Cepheus and Queen Cassiopeia were told to sacrifice Andromeda to Cetus. They had Andromeda chained to a rock near the ocean so that Cetus could devour her. Perseus found Andromeda chained to the rock and learned of her plight. When Cetus emerged from the ocean to devour Andromeda, Perseus managed to slay it. In one version, Perseus drove his sword into Cetus' back. In another version, Perseus used Medusa's head to turn Cetus to stone.

The Cetus is commonly depicted as fishlike, serpentine, with a long muzzle. Alternate depictions may include long ears, horns and legs instead of flippers. It is often depicted fighting Perseus or as the mount of a Nereid.

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