Five nil? Supporter begins to give a cheer (5)
I believe the answer is:
bravo
'a cheer' is the definition.
(I know that bravo is a type of cheer)
'five nil? supporter begins' is the wordplay.
'five' becomes 'V' (Roman numeral).
'nil?' becomes 'O' (O resembles 0).
'supporter' becomes 'bra' (a bra gives support to breasts).
'begins' is a charade indicator (letters next to each other).
'v'+'o'='vo'
'vo' put after 'bra' is 'BRAVO'.
'to give' is the link.
(Other definitions for bravo that I've seen before include "Well done; B (radio)" , "Good man, well done" , "Hurrah!" , "Expression of approval" , "Shout of approval" .)