Kent area, looking north: the other county (5)
I believe the answer is:
essex
'county' is the definition.
(English county)
'kent area looking north the other' is the wordplay.
'kent area' becomes 'se'.
'looking north' says the letters should be written in reverse (going up in a down clue).
'the other' becomes 'sex' (old-fashioned slang term).
'se' reversed gives 'es'.
'es'+'sex'='ESSEX'
(Other definitions for essex that I've seen before include "County NE of London" , "County adjoining London" , "County near London" , "East coast county" , "Queen's favourite" .)