πατήρ
Etym. acc. always πατέρα gen. pl. rarely πατρῶν
I. "a father", Hom., etc.; πατρὸς πατήρ "a grandfather", Il.; τὰ πρὸς πατρός ῀ πατρόθεν, "by the father's side", Hdt.
II. among the gods "Zeus" is called πατήρ, πατὴρ Ζεύς, π. ἀνδρῶν τε θεῶν τε Hom., Hes.; so Ζεὺς π. Aesch.; Ζεῦ πάτερ καὶ θεοί Ar.
III. a respectful mode of addressing elderly persons, Od.
IV. metaph. "the father" of anything, Lat. auctor, π. ἀοιδᾶν Pind., etc.
V. in pl. "fathers", i.e. "forefathers", Hom.; ἐξ ἔτι πατρῶν as an inheritance "from one's fathers", Od.