Dethrone (5)
'dethrone' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for usurp that I've seen before include "Seize wrongfully" , "Dethrone" , "Appropriate without authority" , "Commandeer" , "Wrongfully assume" .)
'dethrone' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for unseat that I've seen before include "Remove from power" , "Remove from horse (or house?)" , "Throw (as a 15?)" , "Cause to fall from the saddle" , "Get out of office" .)