/ Dictionary / Index A adenoma: Meaning and Definition of Find definitions for: ad•e•no•ma Pronunciation: (ad"n-ō'mu), [key] — pl. -mas, -ma•ta a benign tumor originating in a secretory gland. a benign tumor of glandlike structure. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: adenoma (Thesaurus) adenology adenopathy Related Content Daily Word Quiz: sinister Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language