impulsive (adj.)youdaoicibaDictYouDict[impulsive 词源字典]
early 15c., originally in reference to medicine that reduces swelling or humors, from Middle French impulsif or directly from Medieval Latin impulsivus, from Latin impuls-, past participle stem of impellere (see impel). Of persons, "rash, characterized by impulses," from 1847.[impulsive etymology, impulsive origin, 英语词源]