πλαγιοφύλαξ
From LSJ
μισῶ σοφιστὴν ὅστις οὐχ αὑτῷ σοφός → I hate the sage who recks not his own rede, I hate the sage who is not wise for himself, I hate the wise man who is not wise on his own
English (LSJ)
[ῠ], ᾰκος, ὁ, ἡ,
A guarding the flanks of an army on the march, ἶλαι π. D.S.19.82 (v.l. πλᾰγιο-φύλακοι) ; esp. of the corner man in the ῥόμβος (q.v.) of cavalry, Ascl.Tact.7.2,6, Arr.Tact.16.5 ; cf. πλαγυφύλαξ.
German (Pape)
[Seite 623] ακος, ὁ, der die Flanken des Heeres auf dem Marsche bewacht u. schützt, D. Sic. 19, 82.