λευκαίνειν
From LSJ
Ἔστιν τὸ τολμᾶν, ὦ φίλ', ἀνδρὸς οὐ σοφοῦ → Amice, non sapientis es res temeritas → Leichtsinn, mein Freund, passt nicht zu einem weisen Mann
Greek > English (Woodhouse Verbs Reversed)
(see also λευκαίνω): break into ripples, make white