the aperture of a wind instrument into which the player blows directly the tube of a pipe or cigarette holder that a smoker holds in the mouth an acoustic device; the part of a telephone into which a person speaks (especially boxing) equipment that protects an athlete's mouth a part that goes over or into the mouth of a person; "the mouthpiece of a respirator"
The mouthpiece of an organization or person is someone who informs other people of the opinions and policies of that organization or person. Their mouthpiece is the vice-president
{i} piece placed at or in the mouth (in musical instruments, smoking paraphernalia, etc.); opening, nozzle; speaker, representative; teeth protector (Sports); telephone receiver
The part of a pipe held in the lips or between the teeth In a briar, it may be called the stem or bit Nowadays, usually made of vulcanite, but used to be made from amber, bone, horn or cherrywood