(Λαβδακίδαι), a patronymic from Labdacus, and frequently used not only to designate his children, but his descendants in general, and is therefore applied not only to Oedipus, his son, but to Polyneices, Eteocles, and Antigone. The family of the Labdacidae is particularly famous in ancient story, on account of the misfortunes of all that belonged to it. (Soph. Antig. 560; Stat. Theb. 6.451, and many other passages.)
[L.S]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890