hallucination (n.)youdaoicibaDictYouDict[hallucination 词源字典]
"a seeing or hearing something which is not there," 1640s, from Latin hallucinationem (nominative hallucinatio), earlier alucinatio, noun of action from past participle stem of alucinari (see hallucinate). Related: Hallucinations.[hallucination etymology, hallucination origin, 英语词源]