ἐγχλοάω
From LSJ
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)
A to be of a greenish hue, Nic.Th.154. II ἐγχλοᾶσθαι· ἐμφῦναι, Hsch.
German (Pape)
[Seite 713] grüngelblich sein, Nic. Th. 154.