φρούριον
Δελφῖνα νήχεσθαι διδάσκεις: ἐπὶ τῶν ἐν ἐκείνοις τινὰ παιδοτριβούντων, ἐν οἷς ἤσκηται → Teaching dolphins to swim: is applied to those who are teaching something among people who are already well versed in it
English (LSJ)
Dor. φρώριον Inscr.Cret.1 xvi 17.15 (Lato, ii B. C.), τό,
A fort, citadel, A.Eu.919 (lyr.), IG12.93.17, etc.; ἀντὶ τοῦ πόλις εἶναι φρούριον κατέστη Th.7.28: esp. hill-fort, as distd. from a fortified town, Id.2.18, 3.18,51, Lys.12.40, X.Cyr.1.4.16, etc.; βίον ὡς οἰκτρὸν ἐξαντλοῦσιν οἱ τὰ φ. τηροῦντες Men.74; τὰ φ. καὶ τὰ ὅρια τῆς Ἀττικῆς IG22.1028.22. 2 prison, of the body, Pl.Ax.366a. II garrison, of a place, A.Pr.801 (where Sch. also expl. by thing to be guarded against); φυλασσόμεσθα φρουρίοισι E.Or.760 (troch.); πόλεως φ., of the Areopagites, A.Eu.949 (anap.).
German (Pape)
[Seite 1310] τό (kein dim., wie auch der Accent zeigt), 1) Wachposten, fester Platz, Burg od. Schloß mit Besatzung, Festung; Aesch. Eum. 879; Eur. Or. 758; Thuc. 2, 18, oft; τὰ περὶ τὴν Ἀττικὴν φρούρια καθεῖλον Lys. 12, 40; Plat. Rep. VIII, 561 b; Xen. Cyr. 1, 4,16 u. A., u. Sp., ψυχῆς Polemo 1 (XI, 38); Gefängniß, Plat. Ax. 365 e. – 2) die Besatzung, Aesch. Prom. 803 Eum. 909.
