|See also biological clock of or relating to biological processes that occur regularly at about 24-hour intervals, even in the absence of periodicity in the environment|
|[C20: from Latin circa about + diēs day]|
|a gadget; dingus; thingumbob.|
|the offspring of a zebra and a donkey.|
circadian cir·ca·di·an (sər-kā'dē-ən, -kād'ē-, sûr'kə-dī'ən, -dē'-)
Relating to biological variations or rhythms with a cycle of about 24 hours.