precipitous (adj.)youdaoicibaDictYouDict[precipitous 词源字典]
1640s, "rash, headlong," from obsolete French precipiteux (16c.), from Vulgar Latin *praecipitosus, from praecipitare (see precipitation). Related: Precipitously; precipitousness.[precipitous etymology, precipitous origin, 英语词源]