rap-, rav-

(Latin: tearing away, seizing, swift, rapid; snatch away, seize, carry off; from Latin rapere, "to seize by force and to carry off")

usurp, usurps; usurped; usurping (verbs)
1. To take without authorization, often with force: "The duke tried to usurp the throne of the king."
2. To take over or to occupy without the right to do it: "He tried to usurp a neighbor's land."
3. To wrongfully seize another's place, authority, or possession: "Little by little, the assistant started to usurp his boss's authority."
4. To use without authority or right; employ wrongfully: "The magazine usurped copyrighted material for the article."
5. Etymology: from Latin usurpare, "to get possession of, to acquire"; from usus, "use" and rapere, "to seize" (usu-rapos); then through Middle French usurper and via Middle English usurpen.
usurpation (s), usurpations (pl) (nouns)
1. Wrongfully seizing and holding an office or powers by force: "The military usurpation of the throne of the king resulted in a different form of supreme authority."
2. Entry to another person's property without a legal right or permission: "The usurpation of the demonstrators into the shopping center created all kinds of havoc or disruptions for the stores and the shoppers."
3. To seize or to exercise authority or possession of something wrongfully: "The newspapers accused some city council members of a usurpation of the mayor's governing powers."
usurpatory (adjective)
Wrongful or illegal encroachment, infringement, or seizure: "The usurpatory behavior of the police against the student demonstrators resulted in strong condemnations by both students and the media that covered the pepper spraying actions."
usurper (s), usurpers (pl) (nouns)
1. A person who wrongfully or illegally takes over another's place, authority, or possessions unjustly: "The usurpers treated the foreign visitors in a manner that was contrary to decent behavior."
2. Those who take control of a position of power; especially, those who do not have the right to such control or power: "The newspaper described the usurpers as individuals who obtained and maintained authority over the neighborhood by force without any legal authority."

"There were many usurpers in the late Roman Empire; especially, from the so-called crisis of the third century onwards, when political instability became very common."

usurpingly (adverb)
A reference to seizing another's place, authority, or possession wrongfully: "Government regulators criticized the mortgage-servicing industry for usurpingly foreclosing on U.S. homeowners."

"The bank was accused of usurpingly taking the couple's house before they had a chance to make the late payment."