C, anniversary, annual holiday, bicentenary, bicentennial, biennial, birthday, bissextile day, cental, centare, centenarian, centenary, centennial, centennium, centigram, centimeter, centipede, centistere, centred, centref, centrev, centumvir, centumvirate, centurion, century, commemoration, cwt, decennial, diamond jubilee, golden wedding anniversary, gross, hecatomb, holy days, hundred, hundredweight, immovable feast, jubilee, leap year, long hundred, name day, natal day, octennial, one C, quadrennial, quasquicentennial, quincentenary, quincentennial, quinquennial, septennial, sesquicentenary, sextennial, silver wedding anniversary, tercentenary, tercentennial, tricennial, triennial, wedding anniversary

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