Forbidden love old club brought back (5)
I believe the answer is:
taboo
'forbidden' is the definition.
('taboo' can be a synonym of 'forbidden')
'love old club brought back' is the wordplay.
'love' becomes 'o' (In tennis, 'love' means 'zero').
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'club' becomes 'bat' (bat is a kind of club).
'brought back' is a reversal indicator.
'o'+'o'+'bat'='oobat'
'oobat' in reverse letter order is 'TABOO'.
(Other definitions for taboo that I've seen before include "A ban or prohibition of superstitious kind" , "Not to be touched or used, banned for religious reasons" , "Forbidden by social custom" , "unacceptable" , "Socially forbidden" .)