Definify.com

Webster 1913 Edition

Noun.

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.

One who delivers the opinion of others or of another; a spokesman;

as, the

mouthpiece

of his party

Egmont was imprudent enough to make himself the

mouthpiece

of their remonstrance.

Motley.

Noun.

The piece of a musical wind instrument to which the mouth is applied.