County circle upset staff at first (6)
I believe the answer is:
dorset
'county' is the definition.
(I've seen this before)
'circle upset staff at first' is the wordplay.
'circle' becomes 'set' ('set' can be a synonym of 'circle'**).
'upset' shows that the letters should be reversed in order.
'staff' becomes 'rod' (I've seen this before).
'at first' means one lot of letters go next to another.
'rod' in reverse letter order is 'dor'.
'set' after 'dor' is 'DORSET'.
(Other definitions for dorset that I've seen before include "English county -- sorted (anag)" , "South coast county" , "Hardy country" , "area of Portland Bill" , "Coastal county of southern England" .)