/ Dictionary / Index M multiple myeloma: Meaning and Definition of Find definitions for: mul'tiple myelo'ma Pronunciation: [key] a malignant plasma cell tumor of the bone marrow that destroys bone tissue. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Multiple Mirror Telescope multiple neuritis Related Content Daily Word Quiz: denizen Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language