Pole about to join clique in the county (6)
I believe the answer is:
dorset
'county' is the definition.
(I've seen this before)
'pole about to join clique' is the wordplay.
'pole' becomes 'rod' ('rod' can be a synonym of 'pole'**).
'about' says the letters should be written backwards.
'to join' says to put letters next to each other.
'clique' becomes 'set' (I've seen this before).
'rod' backwards is 'dor'.
'dor'+'set'='DORSET'
'in the' acts as a link.
(Other definitions for dorset that I've seen before include "County adjoining 1" , "Weymouth's county" , "Coastal county of southern England" , "A SW county" , "Strode (anag.)" .)