ἔνδεινος
From LSJ
ἢ λέγε τι σιγῆς κρεῖττον ἢ σιγὴν ἔχε → either say something better than silence or keep silence (Menander)
Greek (Liddell-Scott)
ἔνδεινος: -ον, = δεινός, Ὠριγ. IV, 409Β.
Spanish (DGE)
-ον
terrible neutr. sg. compar. como adv. terriblemente ἡ πόλις δὲ ἐνδεινότερον ἐξεπέπληκτο ὑπὸ δείματος Them.Or.4.56a.
Russian (Dvoretsky)
ἔνδεινος: Hom. ap. Plut. = δεινός.