Debauched party (4)
I believe the answer is:
orgy
'debauched party' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for orgy that I've seen before include "Bacchanalian party" , "Rumpy-pumpy party" , "overindulgence" , "Riotous celebration" , "Drunken revelry" .)