Medical Dictionary


adj ul·tra·di·an \əl-ˈtrād-ē-ən\

Definition of ULTRADIAN

:  being, characterized by, or occurring in periods or cycles (as of biological activity) that are repeated frequently (as every 90 to 100 minutes) throughout a 24-hour period <ultradian rhythms>—compare circadian, infradian
March 29, 2015
discomfit Hear it
To thwart or disconcert
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