Circadian rhythm refers to the natural, internal processes that regulate the sleep-wake cycle and other physiological functions over a roughly 24-hour period. The term “circadian” comes from the Latin words “circa,” meaning “around,” and “diem,” meaning “day,” reflecting the cycle’s alignment with the Earth’s day-night cycle. Here are some key aspects of circadian rhythms: Overall, circadian rhythms are crucial for maintaining overall health and well-being, influencing sleep, energy levels, and various bodily functions.