/ Dictionary / Index C cyesis: Meaning and Definition of Find definitions for: cy•e•sis Pronunciation: (sī-ē'sis), [key] — pl. -ses pregnancy. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Cydnus cygnet 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