Bacchanal (4)
I believe the answer is:
orgy
'bacchanal' is the definition.
(I know that bacchanal can be written as orgy)
This is all the clue.
(Other definitions for orgy that I've seen before include "Excessive indulgence" , "debauched scene" , "Debauched party" , "Gory (anag.)" , "Bacchanal" .)