I. Act., to harden, render hard (only postclass.); “in the trop. signif.: obdurare se contra manifestam veritatem,” Lact. 1, 1, 23: “obdurata patientia,” Nazar. Pan. ad Const. 13: “obdurata nequitia,” Cod. Just. 10, 19, 2: “obdurata verecundia,” Capitol. Pert. 9.—Esp., to harden the heart against God (eccl. Lat.): “obdurare corda,” Vulg. Heb. 3, 8; id. Psa. 94, 8; id. Deut. 15, 7.—Pass.: “ut non obduretur quis vestrum,” Vulg. Heb. 3, 13.—
II. Neutr., to be hard or hardened; only trop., to hold out, persist, endure: “pernegabo atque obdurabo,” Plaut. As. 2, 2, 56: “persta, atque obdura,” Hor. S. 2, 5, 39; Cat. 8, 11: “perfer et obdura,” Ov. Tr. 5, 11, 7.— Impers. pass.: quare obduretur hoc triduum, * Cic. Att. 12, 3.