Word.ws English Dictionary

circadian

/səˈkeɪ.dɪ.ən/US/sɚˈkeɪ.di.ən/

circadian adjective: of, relating to, or showing rhythmic behaviour with a period of approximately 24 hours; especially of a biological process.

Adjective

circadian (not comparable)

  1. Of, relating to, or showing rhythmic behaviour with a period of approximately 24 hours; especially of a biological process.
    • 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

circadian meaning in Tamil

circadian in Tamil

நாடொறு

Examples of circadian in a sentence

  • 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.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 addition, the truck driver’s schedule involved sleeping at irregular times, including times when the body’s circadian rhythms are geared toward being awake.2024, NTSB, Highway Investigation Report, HIR-24-05:

Synonyms of circadian

All synonyms of circadian

Origin of circadian

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

Words formed from circadian

Phrases with circadian

Questions about circadian

What does circadian mean?
Circadian means of, relating to, or showing rhythmic behaviour with a period of approximately 24 hours; especially of a biological process.
What is circadian in Tamil?
Circadian in Tamil is நாடொறு. See Circadian meaning in Tamil.
How do you use circadian in a sentence?
The most obvious circadian rhythm is the daily cycle of sleep and activity.
What part of speech is circadian?
Circadian is an adjective.
How do you pronounce circadian?
Circadian is pronounced /səˈkeɪ.dɪ.ən/ (UK).

Words near circadian in the dictionary

  1. CIRB
  2. circ
  3. circ.
  4. circa
  5. circadially
  6. circadian
  7. circadian clock
  8. circadian clocks
  9. circadian dysrhythmia
  10. circadian rhythm
  11. circadian rhythms

Source and license

Adapted from Wiktionary: circadian (page history and authors); circadian (Tamil Wiktionary) (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Pronunciation audio from Wikimedia Commons, each file under its own free license: LL-Q1860 (eng)-Vealhurl-circadian.wav.

Cite this entry: “circadian.” Word.ws, https://word.ws/circadian. Based on Wiktionary, CC BY-SA 4.0.