righteous (adj.)youdaoicibaDictYouDict[righteous 词源字典]
early 16c. alteration of rightwise, from Old English rihtwis, from riht (see right) + wis "wise, way, manner" (see wise (adj.)). Suffix altered by influence of courteous, etc. Meaning "genuine, excellent" is 1942 in jazz slang. Related: Righteously.[righteous etymology, righteous origin, 英语词源]