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
adj.
Full-grown: P. τέλεος, V. ἐκτελής. Well-grown: P. and V. εὐτραφής (Plat.), Ar. and V. εὐφυής.