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infradian

American  
[in-frey-dee-uhn] / ɪnˈfreɪ di ən /

adjective

Physiology.
  1. of or relating to a biorhythm or regular biological cycle having a period of more than 24 hours, such as the migration of birds or the human menstrual cycle.


Etymology

Origin of infradian

First recorded in 1965–70; infra- ( def. ) + Latin di(ēs) “day” + -an ( def. )