circadian

Definition

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

Etymology

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

Example Sentences

• "The circadian clock is involved in the regulation of the diurnal sleep-wake cycle, […]."
• "To summarize, the circadian system, particularly the SCN, controls the circadian pattern of melatonin release in mammals."
• "The most obvious circadian rhythm is the daily cycle of sleep and activity."