Practise for a performance (8)
I believe the answer is:
rehearse
'practise for a performance' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for rehearse that I've seen before include "Practise like actor" , "Prepare for a stage production" , "Practise before a public performance" , "prepare for performance" , "Practice a play" .)