Completely plunder (7)
I believe the answer is:
despoil
'completely plunder' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for despoil that I've seen before include "Plunder, devastate" , "Plunder - I sloped (anag)" , "Plunder (a place)" , "Steal from (a place)" , "Plunder, rob" .)