/ Dictionary / Index M mib: Meaning and Definition of Find definitions for: mib Pronunciation: (mib), [key] — n. a playing marble, esp. one that is not used as a shooter. the game of marbles. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: mib (Thesaurus) miazine mic Related Content Daily Word Quiz: pugilist Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language