A northern girl at university in old French province (5)
I believe the answer is:
anjou
'old french province' is the definition.
(I've seen this before)
'a northern girl at university' is the wordplay.
'northern' becomes 'n' (abbreviation e.g. N. Ireland).
'girl' becomes 'jo' (woman's name).
'at' means one lot of letters go next to another.
'university' becomes 'u' (abbreviation for university).
'a'+'n'+'jo'+'u'='ANJOU'
'in' is the link.
(Other definitions for anjou that I've seen before include "Whence Angevins came" , "Old province of the Loire valley, an English possession 1154-1204" , "Old French province" , "Historical French province" , "Historic province of the Loire valley" .)