/ Dictionary / Index M MIA: Meaning and Definition of Find definitions for: MIA Pronunciation: [key] — pl. MIA's, MIAs missing in action. a soldier declared missing in action. M.I.A. Pronunciation: [key] Master of International Affairs. missing in action. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. MI6 Miami Related Content Daily Word Quiz: belligerent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language