periodical

period +‎ -ical.

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periodical (plural periodicals)

1. A publication issued regularly, but less frequently than daily.
2. 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.

• (a publication that appears at fixed intervals): serial

periodical (comparative more periodical, superlative most periodical)

1. Periodic.
   • Sir J. Herschel

     The periodical times of all the satellites.

   • 2012 March-April, Anna Lena Phillips, “Sneaky Silk Moths”, in American Scientist‎, volume 100, number 2, page 172:

     Last spring, the periodical cicadas emerged across eastern North America. Their vast numbers and short above-ground life spans inspired awe and irritation in humans—and made for good meals for birds and small mammals.

2. Published at regular intervals of more than one day, especially weekly, monthly, or quarterly.
   • Courthope

     To influence opinion through the periodical press.

3. Of, or relating to such a publication.

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