ἢ λέγε τι σιγῆς κρεῖττον ἢ σιγὴν ἔχε → either say something better than silence or keep silence (Menander)
δειματόω, ἐκφοβέω, ἐκδειματόω, ἐκδειμαίνω, ἐμφοβέω, ἐκταράσσω