/ Dictionary / Index O osteoma: Meaning and Definition of Find definitions for: os•te•o•ma Pronunciation: (os"tē-ō'mu), [key] — pl. -mas, -ma•ta a benign tumor composed of osseous tissue. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: osteoma (Thesaurus) osteology osteomalacia Related Content Daily Word Quiz: cygnet Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language