παράφραγμα · paraphragma — LSJ
breastwork on the top of a wall or mound, mostly in pl., Th. 4.115 ; of a ship, bulwarks, Id. 7.25 ; screen or curtain, Pl. R. 514b ; τὰ τοῦ βουλευτηρίου π. App. BC 2.118.
metaph. in sg., barrier, π. καὶ ἐμπόδιον Dam. Pr. 400.