Surplus pennies pocketed by Brexit opponent (9)
I believe the answer is:
remainder
'surplus' is the definition.
(I've seen this before)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for remainder that I've seen before include "Surplus" , "Leftovers" , "deposit" , "set of unsold books" , "Left-over" .)