early 20th century (originally with reference to a condition in which fantasy dominates over reality, regarded as a symptom of schizophrenia and other disorders): from Greek autos ‘self’ + -ism
20世紀初頭(元々は統合失調症などの症状とされる、空想が現実を支配する状態を指す):ギリシャ語のautos「自己」+-ismから。