A.ao and εω; Dor. ᾿Αΐδας, α, used by Trag., in lyr.and anap.: gen. ῎Αϊδος, dat. ῎Αϊδι, Hom., Trag., v. infr.: (perh. ἀ- priv., ἰδεῖν):—in Hom. only as pr.n. Hades, “Ζεὺς καὶ ἐγώ, τρίτατος δ᾽ Αΐδης” Il.15.188, cf.Hes.Th.455:—εἰν᾽ Αΐδαο δόμοισι in the nether world, Od.4.834; freq. εἰν, εἰς Αΐδαο (sc. δόμοις, δόμους), as Il.22.389, 21.48; εἰν Ἄϊδος Il 24.593; Trag. and Att. ἐν Ἅιδου, εἰς Ἅιδου (sc. οἴκῳ, οἶκον), S.Aj.865, Ar.Ra.69, etc.; Ἄϊδόσδε, Adv. to the nether world, Il.7.330, etc.; παρ᾽ Ἅιδῃ, παρ᾽ Ἅιδην, OT972, OC 1552:—hence,
2. place of departed spirits, first in Il.23.244 “εἰσόκεν αὐτὸς . . Ἄϊδι κεύθωμαι; ἐπὶ τὸν ᾄδην” Luc.Cat.14; “εἰς ἀΐδην” AP11.23; “ἐν τῷ ᾄδῃ” Ev.Luc.16.23.