Epicurean academic involved in robbery (8)
I believe the answer is:
hedonist
'epicurean' is the definition.
(thesaurus)
'academic involved in robbery' is the wordplay.
'academic' becomes 'don' (I've seen this before).
'involved in' means one lot of letters goes inside another.
'robbery' becomes 'heist' (heist is a kind of robbery).
'don' inserted within 'heist' is 'HEDONIST'.
(Other definitions for hedonist that I've seen before include "pagan" , "Seeker of sensual pleasure" , "playboy" , "A seeker after luxury" , "Extreme pleasure-seeker" .)