Lewis Short
(verb) : ob-dūro, āvi, ātum, 1, and n.
* 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.
* 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.
Charlton T. Lewis, Charles Short, A Latin Dictionary