usurpation

n. unlawful takeover of control or of government

"Usurp" redirects here. You might be also looking for Wikipedia:Changing username/Usurpations. This article is about a person asserting official authority. For the computer game, see Usurper (game). Usurper (lat. usurpare = to seize for use, to use) is a derogatory term used to describe either an illegitimate or controversial claimant to the throne in a monarchy, or a person who succeeds in establishing himself as a monarch without inheriting the throne, or any other person asserting official authority without having been delegated that authority. It may also be be applied to an official acting ultra vires, outside his authority or jurisdiction.
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Noun
1. entry to another's property without right or permission
(synonym) trespass, encroachment, violation, intrusion
(hypernym) wrongdoing, wrongful conduct, misconduct, actus reus
(hyponym) inroad
2. wrongfully seizing and holding (an office or powers) by force (especially the seizure of a throne or supreme authority); "a succession of generals who ruled by usurpation"
(hypernym) capture, gaining control, seizure
(derivation) assume, usurp, seize, take over, arrogate

n. usurpation, unlawful takeover of control or of government; spoofing (Computers)

(n.)
Use; usage; custom.
  

(n.)
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.