periodical UK /ˌpɪəɹiˈɒdɪkl̩/US /ˌpɪɹiˈɑdɪkl̩/adjective 3noun 2forms 3 adjective3 •Periodic.The periodical times of all the satellites. — 1838 •Published at regular intervals of more than one day, especially weekly, monthly, or quarterly.influence opinion through the periodical press. — 1882 •Of, or relating to such a publication. noun2 •A publication issued regularly, but less frequently than daily. •A regularly issued thematic publication that contains the most current information in its field, often the primary means for communication of original scholarship or creative work at the cutting edge of research in its field. formsperiodicals · more periodical · most periodical