circadian

CEFRB2

/səˈkeɪ.dɪ.ən/

adjective

Türkçe translations

Translating…

In plain English

01
adjective
Relating to a natural cycle of about twenty-four hours.
02
adjective
Extra detail
Of, relating to, or showing rhythmic behaviour with a period of approximately 24 hours; especially of a biological process.

Examples

At a glance

Sits at B2 on the CEFR scale

Also pronounced

Deep Dive

In context

The circadian clock is involved in the regulation of the diurnal sleep-wake cycle, […].
To summarize, the circadian system, particularly the SCN, controls the circadian pattern of melatonin release in mammals.
The most obvious circadian rhythm is the daily cycle of sleep and activity.

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The word in print, with each source given in full.

The circadian clock is involved in the regulation of the diurnal sleep-wake cycle, […].
2000, Arnold Sameroff, et al: Handbook of Developmental Psychopathology, page 310
To summarize, the circadian system, particularly the SCN, controls the circadian pattern of melatonin release in mammals.
2002, Jill B. Becker, Behavioral Endocrinology, page 483
The most obvious circadian rhythm is the daily cycle of sleep and activity.
2005, Paul Martin, Counting Sheep: The Science and Pleasures of Sleep and Dreams, page 114
Circadian clocks developed early in evolution in single-celled organisms, before the animal and plant kingdom split from one another. The original clocks probably functioned to protect the cells from damage induced by high UV radiation.
2014 April 5, “Quite interesting: A quietly intriguing column from the brains behind QI, the BBC quiz show. This week; QI orchids you not”, in The Daily Telegraph (Weekend), page W22
In addition, the truck driver’s schedule involved sleeping at irregular times, including times when the body’s circadian rhythms are geared toward being awake. He was also awake at times when his circadian rhythms were geared toward being asleep. The time of the crash, about 1:36 a.m., is when sleepiness tends to be greater and performance capabilities are lower.
2024, NTSB, Highway Investigation Report, HIR-24-05

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From Latin circā (“around”) + diēs (“day”) + English -an. Compare circannual.