untrue (adj.)youdaoicibaDictYouDict[untrue 词源字典]
Old English untreowe "unfaithful" (of persons), from un- (1) "not" + true (adj.). Similar formation in Middle Dutch ongetrouwe, Middle Low German ungetruwe, Old High German ungitriuwi, Old Norse utryggr. Meaning "contrary to facts" is attested from c. 1300.[untrue etymology, untrue origin, 英语词源]