μεταλλάσσειν

From LSJ

μὴ εἴπῃς ὠς οὐκ ἔστι Ζεύς → don't say that there is no Zeus

Source

Greek > English (Woodhouse Verbs Reversed)

(see also μεταλλάσσω): change, quit, change into, turn into

Lexicon Thucydideum

permutare, to exchange, 8.70.1.