County is finished with girl (7)
I believe the answer is:
donegal
'county' is the definition.
(county of Ireland)
'finished with girl' is the wordplay.
'finished' becomes 'done' (both can mean completed).
'with' says to put letters next to each other.
'girl' becomes 'gal'.
'done'+'gal'='DONEGAL'
'is' is the link.
(Other definitions for donegal that I've seen before include "town and county" , "County of NW Ireland" , "Northernmost Irish county" , "Ireland's northmost county" , "Lean dog (anag) - Irish county" .)