All-night party (4)
I believe the answer is:
rave
'all-night party' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for rave that I've seen before include "Rage" , "Talk incoherently" , "Laudatory sort of review - quite a rant" , "Modern youth dance - sounds hysterical" , "Fume" .)