Reversal of an act on a contest? (9)
I believe the answer is:
turnabout
'reversal' is the definition.
(I know that reversal can be written as turnabout)
'an act on a contest?' is the wordplay.
'an' becomes 'a'.
'act' becomes 'turn' (theatre).
'on' is a charade indicator (letters next to each other).
'a contest?' becomes 'bout' (a bout is a boxing match).
'a' put after 'turn' is 'turna'.
'turna'+'bout'='TURNABOUT'
'of' acts as a link.
(Other definitions for turnabout that I've seen before include "complete change of policy" , "That makes a change" , "Total change of policy" , "change of heart" .)