County for male deer (5)
I believe the answer is:
bucks
This clue is a double definition.
'county' is the first definition.
(short for Buckinghamshire)
'male deer' is the second definition.
(I've seen this before)
'for' is the link.
(Other definitions for bucks that I've seen before include "County to northwest of London (abbrev.)" , "County (abbreviation)" , "Animals; a county (abbr.)" , "Dollars" , "overseas money" .)