circadian
adjective
cir·ca·di·an
sər-ˈkā-dē-ən 
: being, having, characterized by, or occurring in approximately 24-hour periods or cycles (as of biological activity or function)
circadian rhythms in activity
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In 1959, a scientist formed the word circadian from the Latin words circa ("about") and dies ("day"), and it caught on quickly. Most often, it's seen and heard in the term circadian rhythm, which refers to the inherent cycle of about 24 hours that appears to control various biological processes, such as sleep, wakefulness, and digestive activity. If you want to impress your friends, you can also use the term circadian dysrhythmia, a fancy synonym of jet lag.
Examples of circadian in a Sentence
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Physical activity can also help to prevent nighttime wandering, a common danger among Alzheimer’s patients due to dysfunction in their circadian rhythms, according to Sherri Snelling, a gerontologist and spokesperson for Comfort Keepers in California.
—
Melissa Rudy, Fox News, 8 Nov. 2024
Shift workers often work at schedules that are misaligned with the circadian rhythm of the human body.
—Lieke Ten Brummelhuis, Forbes, 5 Nov. 2024
Our body’s internal clock, or circadian rhythm, regulates our sleep-wake cycles.
—Anita Bhagwandas, Condé Nast Traveler, 29 Oct. 2024
Melatonin is a hormone made by our bodies' pineal gland that helps regulate our circadian rhythms, the natural patterns our bodies experience in a 24-hour cycle.
—Michael Franco, New Atlas, 4 Nov. 2024
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Melissa Rudy, Fox News, 8 Nov. 2024
Shift workers often work at schedules that are misaligned with the circadian rhythm of the human body.
—Lieke Ten Brummelhuis, Forbes, 5 Nov. 2024
Our body’s internal clock, or circadian rhythm, regulates our sleep-wake cycles.
—Anita Bhagwandas, Condé Nast Traveler, 29 Oct. 2024
Melatonin is a hormone made by our bodies' pineal gland that helps regulate our circadian rhythms, the natural patterns our bodies experience in a 24-hour cycle.
—Michael Franco, New Atlas, 4 Nov. 2024
See all Example Sentences for circadian
Dictionary Entries Near circadian
Cite this Entry
“Circadian.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/circadian. Accessed 28 Nov. 2024.
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circadian
adjective
cir·ca·di·an
(ˌ)sər-ˈkad-ē-ən, -ˈkād-; ˌsər-kə-ˈdī-ən, -ˈdē-
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