Confiscate (7)
I believe the answer is:
impound
'confiscate' is the definition.
(I know that confiscate can be written as impound)
This is all the clue.
(Other definitions for impound that I've seen before include "Seize goods for an infringement of the law" , "Seize and take into legal custody" , "Sequester" , "Shut up" , "Seize (goods) legally" .)