Usurpation /(?)/

U·sur·pa·tion

Usurpation

n.
  1. 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.
    He contrived their destruction, with the usurpation of the regal dignity upon him.
    — Sir T. More.
    A law [of a State] which is a usurpation upon the general government.
    — O. Ellsworth.
    Manifest usurpation on the rights of other States.
    — D. Webster.
  2. Use; usage; custom. [Obs.]