/ Dictionary / Index C circannual: Meaning and Definition of Find definitions for: circ•an•nu•al Pronunciation: (sûr-kan'y-ul), [key] — adj. Biol. noting or pertaining to a biological activity or cycle that recurs yearly. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. circadian Circassia Related Content Daily Word Quiz: impetuous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language