puritan
noun [ C ] uk/ˈpjʊə.rɪ.tən/ us/ˈpjʊr.ɪ.t̬ən/
清教徒式的人;禁欲者;道学先生
someone who believes that it is important to work hard and control yourself, and that pleasure is wrong or unnecessary
Despite his apparent liberal views, he's really something of a puritan/he has a puritan streak. 尽管他表面上持自由派观点,但实际上他有点像个清教徒。
Synonym: prude