·noun Use; usage; custom.
II. Usurpation ·noun The act of usurping, or of seizing and enjoying; an authorized, arbitrary assumption and exercise of power, especially an infringing on the rights of others; specifically, the illegal seizure of sovereign power;
— commonly used with of, also used with on or upon; as, the usurpation of a throne; the usurpation of the supreme power.