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

Words nearby circadian

Cipro, ciprofloxacin, cir., circ, circa, circadian, circadian rhythm, circannual, Circassia, Circassian, Circassian walnut

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use circadian in a sentence

In the daytime, light enters the retina and stimulates the hypothalamus, the part of the brain that maintains circadian rhythms, letting the body know it’s time to be awake and functioning.
Can a happy lamp help cure your winter blues?|Erin Fennessy|January 25, 2021|Popular-Science
Our bodies’ circadian rhythms function best with established routines, predictable light, and lower noise levels.
Bedside lights that do more than shine|PopSci Commerce Team|January 14, 2021|Popular-Science
While blue light has gotten a bad rap for disrupting our circadian rhythms, research suggests that it’s only stimulating when it’s too bright.
To take the most relaxing bath ever, add some healthy tips|Rachel Feltman|January 3, 2021|Popular-Science
While it’s true that our circadian rhythms directly affect our digestive activity, as biologist Lawrence Scheving detailed in the journal Gastroenterology, those individual patterns rarely sync up with the time on a clock.
Five myths about nutrition|Jessica Wilson|December 31, 2020|Washington Post

The full cycle was 18 hours, which meant the timing of our circadian cycles were constantly changing.
How a Nuclear Submarine Officer Learned to Live in Tight Quarters - Issue 94: Evolving|Steve Weiner|December 30, 2020|Nautilus
Bright light is what keeps our circadian rhythms in good order.
Fight Seasonal Affective Disorder With This New Tracker|DailyBurn|November 7, 2014|DAILY BEAST
Lighting signals your body's circadian rhythm and can have a strong effect on your mood.
Change Your Sense: Biohacking for Beginners|Ari Meisel|March 18, 2014|DAILY BEAST
“One of the most important things you can do for your sleep is to have a routine to keep your circadian rhythm normal,” says Suh.
Can’t Sleep? Your Guide to a Better Night’s Rest|DailyBurn|January 24, 2014|DAILY BEAST
In general, Tb's showed a marked circadian cycle in phase with photoperiod.
Metabolic Adaptation to Climate and Distribution of the Raccoon Procyon Lotor and Other Procyonidae|John N. Mugaas

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

circadian

Origin of circadian

Words nearby circadian

Words related to circadian

How to use circadian in a sentence

British Dictionary definitions for circadian

Word Origin for circadian