/ Dictionary / Index C cystoma: Meaning and Definition of Find definitions for: cys•to•ma Pronunciation: (si-stō'mu), [key] — pl. -mas, -ma•ta a cystic tumor. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. cystolith cystometer Related Content Daily Word Quiz: lunar Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language