Celebrity retired from the Mafia (4)
I believe the answer is:
fame
'celebrity' is the definition.
(celebrity can mean the quality of being famous)
'retired from the mafia' is the wordplay.
'retired' says the letters should be written backwards.
'from' indicates the answer is hidden within the clue.
'emaf' is hidden within 'the mafia'.
'emaf' reversed gives 'FAME'.
(Other definitions for fame that I've seen before include "Celebrity; stage musical" , "Musical - stardom" , "Note" , "''... is the spur that the clear spirit doth raise (Lycidas, John Milton)" , "Prominence" .)