Gave back theatre subsidy? (6)
I believe the answer is:
repaid
'gave back' is the definition.
('repay' can be a synonym of 'give back')
'theatre subsidy?' is the wordplay.
'theatre' becomes 'rep' (repertory theatre).
'subsidy?' becomes 'aid' (subsidy is a kind of aid).
'rep'+'aid'='REPAID'
(Other definitions for repaid that I've seen before include "Diaper (anag.)" , "Returned" , "Gave back money owed" , "Recompensed" , "Refunded or rewarded" .)