Spoils from Waterloo taken (4)
I believe the answer is:
loot
'spoils' is the definition.
(both can mean a reward or proceeds)
'from waterloo taken' is the wordplay.
'from' indicates a hidden word.
'LOOT' is hidden within 'waterloo taken'.
(Other definitions for loot that I've seen before include "Booty, spoils" , "rifle" , "Steal (goods); money" , "Booty; sack" , "Swag, booty" .)