: any of a group of wind instruments (such as a clarinet, flute, oboe, or saxophone) that are characterized by a cylindrical or conical tube of wood or metal usually ending in a slightly flared bell, that produce tones by the vibration of one or two reeds in the mouthpiece or by the passing of air over a mouth hole, and that usually have finger holes or keys by which the player may produce all the tones within an instrument's range