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Related to circadian: Circadian clock, Circadian rhythm sleep disorder


 (sər-kā′dē-ən, -kăd′ē-, sûr′kə-dī′ən, -dē′-)
adj. Biology
Relating to or exhibiting approximately 24-hour periodicity.

[Latin circā, around; see circa + Latin diēs, day; see dyeu- in Indo-European roots.]

cir·ca′di·an·ly adv.


(Biology) of or relating to biological processes that occur regularly at about 24-hour intervals, even in the absence of periodicity in the environment. See also biological clock
[C20: from Latin circa about + diēs day]


(sɜrˈkeɪ di ən, ˌsɜr kəˈdi ən)

of or pertaining to rhythmic cycles recurring at approximately 24-hour intervals: the circadian biological clock.
[1955–60; < Latin circā about + di(ēs) day + -an1]
cir•ca′di•an•ly, adv.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.circadian - of or relating to biological processes occurring at 24-hour intervals; "circadian rhythms"


[səˈkeɪdɪən] ADJcircadiano
circadian cycleciclo m circadiano


adj circadiano; — rhythm ritmo circadiano
References in periodicals archive ?
Elsevier announces a new open access journal: Neurobiology of Sleep and Circadian Rhythms
delays the internal circadian clock that tells us when to get ready for sleep and when to prepare to wake up.
In this regard, we would like to highlight two sources of animal diversity that could be relevant: 1) the differential--and genetically codetermined--circadian propensity for activity and rest with which the mice are born, and 2) the differential stability of circadian rhythms in later life stages of mice, to which perinatal photoperiods may contribute.
We will functionally define the daily oscillating molecular signature(s) of leukocytes and endothelial cells with novel proteomics approaches and thus identify a circadian traffic code that dictates the rhythmic migration of leukocyte subsets to specific organs under steady-state and inflammatory conditions with pharmacological and genetic tools.
George Brainard from Thomas Jefferson University, which revealed that the human eye possesses a set of non-vision photoreceptors that helps regulate circadian rhythm and production of important neurochemicals, impacting everything from sleep and mood to the health of the human immune system.
ISLAMABAD -- Lipoic acid, found at higher levels in organ meats and leafy vegetables such as spinach and broccoli, may help reset and synchronise circadian rhythms or the "biological clock" found in most life forms, says a study.
Recent studies have demonstrated a link in energy regulation to circadian clock patterns, suggesting a potential role of food timing in the role of obesity.
Washington, May 22 ( ANI ): Researchers have said that a disruption of circadian rhythms, when combined with a high-fat, high-sugar diet, may contribute to inflammatory bowel disease and other harmful conditions.
Fluctuations in physiology and behavior move to the beat of the circadian clock.
A practical approach to circadian rhythm sleep disorders.
Apparently, it's all down to your circadian rhythm, which is your natural wake and sleep pattern.
Circadian timing, the ability of an organism to temporally synchronize endogenous function with the external environment, has been found in every species and in many different cell types.