Administrative centre fighting against vote for levy (7,5,3)
I believe the answer is:
capital gains tax
'levy' is the definition.
(capital gains tax is a kind of levy)
'administrative centre fighting against vote' is the wordplay.
'administrative centre' becomes 'capital' (I can't justify this - if you can you should believe this answer much more).
'fighting' indicates an anagram.
'vote' becomes 'x' (how votes are marked).
'against' with letters rearranged gives 'gainsta'.
'capital'+'gainsta'+'x'='CAPITAL GAINS TAX'
'for' is the link.
Can you help me to learn more?
(Other definitions for capital gains tax that I've seen before include "that reduces profits" , "may reduce profits" , "CGT in full" .)