Clytemnestra
in Greek mythology, daughter of King Tyndareus and Leda, and half-sister of Helen. During the absence of Agamemnon in the war against Troy she bestowed her favors on Ægisthus, and, in connection with him, murdered her husband, Agamemnon, on his return from Troy, and with her paramour, governed Mycenæ for seven years. Her son Orestes killed them both.