Go and party (4)
I believe the answer is:
bash
I believe this clue is a double definition.
'go' is the first definition.
(I've seen this before)
'party' is the second definition.
(I've seen this before)
'and' acts as a link.
(Other definitions for bash that I've seen before include "Strike violently" , "Heavy blow; party" , "Party - punch" , "knock" , "Try - rave-up" .)