reticent: [19] The ultimate source of reticent is Latin tacēre ‘be silent’ (source of English tacit and taciturn). Combination with the intensive prefix re- produced reticēre ‘keep silent’, whose present participle gave English reticent. It was preceded into the language by over two hundred years by the derived noun reticence. => tacit, taciturn[reticent etymology, reticent origin, 英语词源]