κατασιωπητέον
From LSJ
μηδὲν κοτυλίζειν, ἀλλὰ καταπάττειν χύδην → not to sell by the cupful, but to dole out indiscriminately | not to sell by retail but wholesale
English (LSJ)
one must keep silence, Isoc.12.96.
Greek (Liddell-Scott)
κατασιωπητέον: ῥημ. ἐπίθ., πρέπει νὰ κατασιωπᾷ τις περί τινος, περί τινος κατασιωπητέον Ἰσοκρ. 252D.
French (Bailly abrégé)
adj. verb. de κατασιωπάω.