u ‧ surp /juːˈzɜːp $ -ˈsɜːrp/ BrE AmE verb [transitive]
[ Date: 1300-1400 ; Language: Old French ; Origin: usurper , from Latin usurpare 'to take something by using it' , from usus ( ⇨ ↑ use 1 ) + rapere 'to seize' ]
formal to take someone else’s power, position, job etc when you do not have the right to:
There were a couple of attempts to usurp the young king.
—usurper noun [countable]
—usurpation /ˌjuːzɜːˈpeɪʃ ə n $ -sɜːr-/ noun [uncountable]