Meaning

noun (psychiatry) an abnormal absorption with the self; marked by communication disorders and short attention span and inability to treat others as people

originBorrowed from German Autismus, coined by Swiss psychiatrist Eugen Bleuler, first usage dated to 1907 attributed by Carl Jung as an alternative of his for "auto-erotism", although Bleuler himself differentiates the terms in his book Dementia Praecox, first published 1911. From Ancient Greek αὐτός (autós, “self”) + -ισμός (-ismós, “-ism”).

Etymology from Wiktionary, CC BY-SA 3.0