LSJ
ου, ὁ, leader, epith. of gods, as Pan, IG 5(2).93 (Tegea); Hermes, BSA 16.107 (Pisidia); Apollo, Epigr.Gr. 1023.5 (Talmis); fem. προκαθηγέτις, ιδος, epith. of Athena, CIG 4332 (Phaselis); ἀθανάτων π. prob. in Epic.Alex.Adesp. 9 ii 17; Dor. προκαθηγαγέτις Mesom. Mus. 6.
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)