n. The act of shaking or agitating, particularly by the stroke or impact of another body.n. The state of being shaken; the shock occasioned by two bodies coming suddenly and violently into collision; shock; agitation.n. In surgery, injury sustained by the brain or other viscera, as from a fall, a blow, etc.n. In civil law, the act of extorting money or something of value by violence or threats of violence; extortion.