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circadian

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adjective cir·ca·di·an \sər-ˈkā-dē-ən\

Simple Definition of circadian

  • : relating to the regular changes in a person or thing that happen in 24-hour periods

Full Definition of circadian

  1. :  being, having, characterized by, or occurring in approximately 24-hour periods or cycles (as of biological activity or function) <circadian rhythms in activity>

Origin of circadian

Latin circa about + dies day + English 2-an — more at deity


First Known Use: 1959

Other Physiology Terms


Medical Dictionary

circadian

play
adjective cir·ca·di·an \(ˌ)sər-ˈkad-ē-ən, -ˈkād-; ˌsər-kə-ˈdī-ən, -ˈdē-\

Medical Definition of circadian

  1. :  being, having, characterized by, or occurring in approximately 24-hour periods or cycles (as of biological activity or function) <circadian periodicity> <circadian rhythms in behavior or physiological activity>—compare infradian, ultradian




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