/ Dictionary / Index M mass medium: Meaning and Definition of Find definitions for: mass' me'dium Pronunciation: [key] — pl. mass media. any of the means of communication, as television or newspapers, that reach very large numbers of people. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. mass market paperback mass meeting Related Content Daily Word Quiz: labyrinth Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language