1. In a periodical manner.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• perodically,
• periodiocally,
• periododically,
• peridodically,
• periodiacaly,
• perioically,
• perdidically,
• periodially,
• periodaclly,
• peridically,
• periodiacally,
• peroidically,
• perioticaly,
• periodicallly,
• periodicaly,
• periodiclly,
• periodicly,
• periodacally,
• periodocally,
• periotically

• periodic law,
• periodic table,
• periodical,
• periodic acid,
• periodic motion,
• periodic event,
• periodicity.

The adjective form of the word "periodically" is "periodic".

The plural form of "periodically" is "periodically". The word remains unchanged whether it is in singular or plural form.

The singular form of the word "periodically" is "periodicity"