Heather in Stirlingshire (4)
I believe the answer is:
ling
'heather' is the definition.
(synonyms)
'in stirlingshire' is the wordplay.
'in' indicates a hidden word.
'LING' is hidden within 'stirlingshire'.
(Other definitions for ling that I've seen before include "Fish of the cod family" , "Slender food fish" , "Common heather" , "Burbot" , "Cod-like fish" .)