- 1the part of the telephone that is next to your mouth when you speak He put his hand over the mouthpiece and called his wife to the phone.
- 2the part of a musical instrument that you place between your lips
- 3 (usually disapproving) mouthpiece (of/for somebody) a person, newspaper, etc. that speaks on behalf of another person or group of people The newspaper has become the official mouthpiece of the opposition party. The Press Secretary serves as the President's mouthpiece.