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circadian

[ sur-key-dee-uhn ]
/ sɜrˈkeɪ di ən /
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adjective Physiology.
of or relating to a biorhythm or regular biological cycle occurring once every 24 hours, such as waking and sleeping: Exposure to blue light at night can disrupt your circadian rhythm, making your biological clock think it's earlier in the day rather than time for bed.He is doing research related to the circadian cycling of hormones.Compare infradian, ultradian.
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Origin of circadian

First recorded in 1955–60; from circā “about” + Latin di(ēs) “day” + -an;see circa
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use circadian in a sentence

British Dictionary definitions for circadian

circadian
/ (sɜːˈkeɪdɪən) /

adjective
of or relating to biological processes that occur regularly at about 24-hour intervals, even in the absence of periodicity in the environmentSee also biological clock

Word Origin for circadian

C20: from Latin circa about + diēs day
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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