Northern drivers beginning to frequent independent canteen (5)
I believe the answer is:
naafi
'canteen' is the definition.
(Navy, Army and Air Force Institutes run canteens)
'northern drivers beginning to frequent independent' is the wordplay.
'northern' becomes 'n' (abbreviation e.g. N. Ireland).
'drivers' becomes 'AA' (Automobile Association).
'beginning to' says to take the initial letters.
The initial letters of 'frequent independent' is 'fi'.
'n'+'aa'+'fi'='NAAFI'
(Other definitions for naafi that I've seen before include "WW2 canteen" , "Organisation running military canteens" , "Army canteen or shop" , "Military canteen" , "Forces' canteen/shop" .)