πρόφυλαξ

ακος, ὁ
A. advanced guard: οἱ π.,= αἱ προφυλακαί, Th. 3.112, X. An. 2.4.15, etc.
II. officer on guard, Aen.Tact. 22.9, and so prob. in IGRom. 4.455 (Pergam.).— Also fem., Eratosth. Cat. 22.
III. epith. of Apollo, IG 12(7).419.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
An open-access project