Andromeda (ăndrŏmˈĭdə) [key], in Greek mythology, princess of Ethiopia, daughter of King Cepheus, king of Ethiopia, and Cassiopeia. According to most legends Cassiopeia angered Poseidon by saying that Andromeda (or possibly Cassiopeia herself) was more beautiful than the nereids. Poseidon sent a sea monster to prey upon the country; he could be appeased only by the sacrifice of the king's daughter. Andromeda in sacrifice was chained to a rock by the sea; but she was rescued by Perseus, who killed the monster and later married her. Cassiopeia, Cepheus, and Andromeda were all set among the stars as constellations.
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