strait-laced (adj.)youdaoicibaDictYouDict[strait-laced 词源字典]
early 15c., of stays or bodices, "made close and tight;" see strait (adj.) + lace (v.). Figurative sense of "over-precise, prudish, strict in manners or morals" is from 1550s.[strait-laced etymology, strait-laced origin, 英语词源]