ˈɔːɹəl ˈɔɹəl spɒnˈteɪ.ni.əs spɑnˈteɪ.ni.əs said or done without having been planned or written in advance he made a few ad-lib remarks using speech rather than writing an oral tradition an oral agreement based on custom rather than documentation an unwritten law rites … so ancient that they well might have had their unwritten origins in Aurignacian times