Plunder from Waterloo terminus (4)
I believe the answer is:
loot
'plunder' is the definition.
('loot' can be a synonym of 'plunder')
'from waterloo terminus' is the wordplay.
'from' says the answer is hidden in the clue.
'LOOT' is hidden within 'waterloo terminus'.
(Other definitions for loot that I've seen before include "Steal goods as spoils" , "Tool for plundering" , "Booty, spoils" , "Stolen property" , "Orton play; money" .)