induration (n.)youdaoicibaDictYouDict[induration 词源字典]
late 14c., from Old French induracion "hardness, obstinacy" (14c.) or directly from Medieval Latin indurationem (nominative induratio) "hardness (especially of the heart)," noun of action from indurare (see endure).[induration etymology, induration origin, 英语词源]