asperity (n.)youdaoicibaDictYouDict[asperity 词源字典]
c. 1200, asprete "hardship, harshness of feelings," a figurative use, from Old French asperité "difficulty, painful situation, harsh treatment" (12c., Modern French âpreté), from Latin asperitatem (nominative asperitas) "roughness," from asper "rough, harsh," which is of unknown origin; in Latin used also of sour wine, bad weather, and hard times. Figurative meaning "harshness of feeling" in English is attested from early 15c.[asperity etymology, asperity origin, 英语词源]