The part of a musical or other instrument to which the mouth is applied in using it; as, the mouthpiece of a bugle, or of a tobacco pipe.
An appendage to an inlet or outlet opening of a pipe or vessel, to direct or facilitate the inflow or outflow of a fluid.
The part of a pipe the smoker places in his mouth to smoke and balance the pipe.
the tube of a pipe or cigarette holder that a smoker holds in the mouth
the aperture of a wind instrument into which the player blows directly
the top piece of a wind instrument where the mouth blows
The mouthpiece is all of the pipe that is not, technically, the bowl. It is made up of the lip, the draft hole, and the tenon.
The mouthpiece of a woodwind instrument is that part of the instrument which is placed partly in the player's mouth. Single-reed instruments, capped double-reed instruments, and fipple flutes have mouthpieces while exposed double-reed instruments and open flutes do not.
On brass instruments the mouthpiece is the part of the instrument which is placed upon the player's lips. The purpose of the mouthpiece is a resonator, which passes vibration from the lips to the column of air contained within the instrument, giving rise to the standing wave pattern of vibration in the air column. Mouthpieces consist of a simple circular opening which leads, via a semi-spherical or conical cavity, to the main body of the instrument.