circadian

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

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

Full Definition of CIRCADIAN

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

See circadian defined for English-language learners

Origin of CIRCADIAN

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

First Known Use: 1959

Other Physiology Terms

eructation, flux, gustatory, menarche, myopia, senescence, torpor

Rhymes with CIRCADIAN

Acadian, Akkadian, arcadian, Arcadian, Barbadian, Canadian, Grenadian, Orcadian, Palladian

Medical Dictionary

circadian

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

Medical Definition of CIRCADIAN

: 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