wiseacre
noun (especially North American English, old-fashioned, informal)a person who is annoying because they are very confident and think they know a lot 自以为无所不知的人；自以为是的人 Word Originlate 16th cent.: from Middle Dutch wijsseggher ‘soothsayer’, probably from the Germanic base of wit ‘have knowledge’. The assimilation to acre remains unexplained.