Partygoer comparatively bold removing top (5)
I believe the answer is:
raver
'partygoer' is the definition.
(I've seen this before)
'comparatively bold removing top' is the wordplay.
'comparatively bold' becomes 'braver' ('brave' can be similar in meaning to 'bold').
'removing top' means to remove the first letter.
'braver' with its first letter taken away is 'RAVER'.
(Other definitions for raver that I've seen before include "attending acid-house party?" , "Dedicated partygoer" , "one talking incoherently" , "Party animal" , "Uninhibited person" .)