Scores four? Many more (6)
I believe the answer is:
eighty
'scores four?' is the definition.
(four scores - a score is 20)
'many more' is the wordplay.
'many' becomes 'eight' (example).
'more' becomes 'y' (I can't justify this - if you can you should give a lot more credence to this answer).
'eight'+'y'='EIGHTY'
(Other definitions for eighty that I've seen before include "Figure" , "Number" , "score less than a hundred" , "22 [FOUR] scores" , "not many score" .)