undisciplined (adj.)youdaoicibaDictYouDict[undisciplined 词源字典]
late 14c., "untrained," from un- (1) "not" + past participle of discipline (v.). Similar formation in German undisciplinirt, Swedish odisciplinerad. Specific meaning "not subject to military discipline" is attested from 1718.[undisciplined etymology, undisciplined origin, 英语词源]