Daughter of Cepheus (2 syl.) and Cassiopeia. Her mother boasted that the beauty of Andromeda surpassed that of the Nereids; so the Nereids induced Neptune to send a seamonster on the country, and an oracle declared that Andromeda must be given up to it. She was accordingly chained to a rock, but was delivered by Perseus (2 syl.). After death she was placed among the stars. (See Angelica.) Ovid: Metamorphoses, v. 1, etc.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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