αλαλαγή

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

Source

Greek Monolingual

η (Α ἀλαλαγὴ) ἀλαλάζω
δυνατή κραυγή χαράς ή ενθουσιασμού.
[ΕΤΥΜΟΛΟΓΙΑ < ἀλαλἀζω.
ΠΑΡ. μσν. ἀλαλάϊ].