hard-hearted (adj.)youdaoicibaDictYouDict[hard-hearted 词源字典]
also hardhearted, "obdurate, unfeeling," c. 1200, heard-iheorted," from hard (adj.) + hearted. Sometimes in Middle English also meaning "bold, courageous" (c. 1400). Related: Hard-heartedly; hard-heartedness. In late Old English and early Middle English, hard-heort meant both "hard-hearted" (adj.) and "hard-hearted person" (n.).[hard-hearted etymology, hard-hearted origin, 英语词源]