Bishop to wander in the bush (7)
I believe the answer is:
bramble
'bush' is the definition.
(thesaurus)
'bishop to wander' is the wordplay.
'bishop' becomes 'B' (chess abbreviation).
'to wander' becomes 'ramble' (synonyms).
'b'+'ramble'='BRAMBLE'
'in the' acts as a link.
(Other definitions for bramble that I've seen before include "Briar" , "Gather fruit" , "Dog rose" , "Blackberry shrub" , "Wild thorny shrub" .)