Gr. Myth. the wife of Agamemnon: with the aid of her lover Aegisthus she murders her husband and is in turn killed by their son Orestes
See Clytemnestra in American Heritage Dictionary 4
also Cly·taem·nes·tra(klīˌtəm-nĕsˈtrə)
noun Greek Mythology
The wife of Agamemnon who, with the assistance of her lover Aegisthus, murdered him on his return from the Trojan War and was later murdered by her son Orestes.