Get to vote against party (5)
I believe the answer is:
beano
'party' is the definition.
(I've seen this before)
'get to vote against' is the wordplay.
'get' means one lot of letters go next to another.
'to vote' becomes 'bea' (I can't explain this - if you can you should give a lot more credence to this answer).
'against' becomes 'no'.
'bea'+'no' is 'BEANO'.
Can you help me to learn more?
(Other definitions for beano that I've seen before include "Rowdy jollification" , "Enjoyable party" , "rowdy festivity" , "Junket - children's comic" , "Informal party" .)