Abbott-Smith Manual Greek Lexicon
ἄ-θεος (G112)
1 * ἄ-θεος , -ον , in cl. slighting or denying the gods (Plat.; cf. MM, VGT , s.v.); godless, ungodly (Pind.); abandoned by the gods (Soph.) In the NT (cf. Lft. on Ign. ad Trail , §3), of the heathen, without God, not knowing God (Cremer, 281): Eph 2:12 .†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain