n. The act of percussing, or the striking of one body against another with some violence; forcible collision.n. The state of being percussed; the shock produced by the collision of bodies.n. The impression or effect of sound on the ear.n. In medicine: In diagnosis, the method of striking or tapping the surface of the body for the purpose of determining the condition of the organs in the region struck. It is employed chiefly in the diagnosis of diseases of the lungs, heart, and abdominal organs.n. In therapeutics, tapping or striking in various ways with the hand or with an instrument as a therapeutic measure and a part of general massage.n. In music, the production of a tone by a stroke or a blow, as upon any keyboard-instrument.n. In palmistry, the outer side of the hand; the side of the hand opposite the thumb.To arrange (a firearm) by fitting it with a percussion-lock, so that it may be fired by percussion.In medicine, to treat by means of percussion massage.