Arriviste from north in disorderly rave-up (7)
I believe the answer is:
parvenu
'arriviste' is the definition.
(I've seen this before)
'north in disorderly rave-up' is the wordplay.
'north' becomes 'N' (synonyms).
'in' is an insertion indicator.
'disorderly' is an anagram indicator.
'rave'+'up'='raveup'
'raveup' is an anagram of 'parveu'.
'n' put into 'parveu' is 'PARVENU'.
'from' is the link.
(Other definitions for parvenu that I've seen before include "One who climbs" , "One newly risen to wealth or power" , "Social climber" , "Newcomer" , "Arriviste" .)