- 1a : to seize and hold (as office, place, or powers) in possession by force or without right <usurp a throne>
- 2: to take the place of by or as if by force : supplant <must not let stock responses based on inherited prejudice usurp careful judgment>
Usurper (lat. usurpare = to seize for use, to use) is a derogatory term used to describe either an illegitimate or controversial claimant to the power; often, but not always in a monarchy, or a person who succeeds in establishing himself as a monarch without inheriting the throne, or any other person exercising authority unconstitutionally. It may also be applied to an official acting ultra vires, outside his authority or jurisdiction.