flinty (adj.)youdaoicibaDictYouDict[flinty 词源字典]
1530s, "hard-hearted;" 1540s, "hard, impenetrable as flint," from flint + -y (2). Literal sense of "resembling flint" is from 1640s. Related: Flintily; flintiness.[flinty etymology, flinty origin, 英语词源]