Feudal superior in Belgian city (5)
I believe the answer is:
liege
I believe this is a double definition.
'feudal superior' is the first definition.
(I've seen this before)
'belgian city' is the second definition.
(I've seen this before)
'in' is the link.
(Other definitions for liege that I've seen before include "Owing feudal allegiance" , "Belgian, French-speaking city" , "Belgian city or feudal chief" , "Large Belgian city" , "Loyal vassal" .)