mouthpiece

noun ! Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about mouthpiece at Wordnik → Where our words come from →

1. A part that goes over or into the mouth of a person.

   the mouthpiece of a respirator

2. An acoustic device; the part of a telephone into which a person speaks.
3. A spokesperson (as a lawyer).