ἀντιφώνησις
From LSJ
θοῦ, Κύριε, φυλακὴν τῷ στόµατί µου καὶ θύραν περιοχῆς περὶ τὰ χείλη µου → set a guard over my mouth, Lord; keep watch over the door of my lips | set a guard, O Lord, over my mouth; keep watch over the door of my lips (Psalm 140:3, Septuagint version)
English (LSJ)
εως, ἡ,
A answer by letter, POxy.294.12(i A.D.), BGU1204.4(i B.C.).