ENGLISH
REFERENCE

circadian

adj.
C1 Advanced US //sɝˈkeɪdiən// UK //sɜːkˈeɪdiən// cir·ca·di·an

adj. relating to a natural daily cycle of about twenty-four hours. You use this to describe things like your body's sleep-wake pattern.

adj. relating to or occurring approximately every twenty-four hours. Often describes biological rhythms that regulate sleep, metabolism, and other physiological processes.


SIMPLE

My circadian rhythm is out of sync after traveling across several time zones.

CONTEXTUAL

Shift workers often struggle with their health because their circadian rhythms are disrupted by working night shifts.

COMPLEX

The study suggests that exposure to artificial light at night can significantly suppress melatonin production, thereby interfering with the body's natural circadian clock and leading to chronic sleep disorders.

Origin

From the Latin circā (“about”) and diēs (“a day”) with the English suffix -an. Compare circannual.

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