Real Dictionary

circadian
a group or combination of interrelated, interdependent, or interacting elements forming a collective entity; a methodical or coordinated assemblage of parts, facts, concepts, etc [...]
a timepiece, usually free-standing, hanging, or built into a tower, having mechanically or electrically driven pointers that move constantly over a dial showing the numbers of the hours [...]
of or relating to biological processes that occur regularly at about 24- hour intervals, even in the absence of periodicity in the environment [...]
of or relating to biological processes that occur regularly at about 24-hour intervals, even in the absence of periodicity in the environment [...]
the arrangement of the relative durations of and accents on the notes of a melody, usually laid out into regular groups (bars) of beats, the first beat of each bar carrying the stress [...]