/ Dictionary / Index M mouthpiece: Meaning and Definition of Find definitions for: mouth•piece Pronunciation: (mouth'pēs"), [key] — n. a piece placed at or forming the mouth, as of a receptacle or tube. a piece or part, as of an instrument, to which the mouth is applied or which is held in the mouth: the mouthpiece of a trumpet. the part of a bit or bridle, as for a horse, that passes through the animal's mouth. a person, newspaper, etc., that conveys the opinions or sentiments of others; spokesperson. a lawyer, esp. a criminal lawyer. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: mouthpiece (Thesaurus) mouthpart mouth-to-mouth resuscitation Related Content Daily Word Quiz: placid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language