Abbott-Smith Manual Greek Lexicon
σαπρός (G4550)
8 ** σαπρός , -ά -όν [in Sm.: Le 27:14 , 33 * ;] rotten, corrupt, bad, worthless : of trees and fruit (opp. to ἀγαθός, καλός ), Mt 7:17, 18 12:33 Lk 6:43 ; of fish, Mt 13:48 . Metaph., in moral sense: λόγος σ. , Eph 4:29 . "In Hellenistic . . . it became a synonym for αἰσχρός or κακός ," MM, xxii.†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain