early 15c., "a striking, a blow; internal injury, contusion," from Latin percussionem (nominative percussio) "a beating, striking; a beat as a measure of time," noun of action from past participle stem of percutere "to strike hard, beat, smite; strike through and through," from per- "through" (see per) + quatere "to strike, shake" (see quash). Reference to musical instruments is first recorded 1776.