Bishop a godsend for primate (6)
I believe the answer is:
baboon
'for primate' is the definition.
(baboon is a kind of primate)
'bishop a godsend' is the wordplay.
'bishop' becomes 'B' (chess abbreviation).
'godsend' becomes 'boon' (both can mean something very helpful).
'b'+'a'+'boon'='BABOON'
(Other definitions for baboon that I've seen before include "Ground-living primate" , "A large one of 17 across" , "Large long-nosed Arabian or African monkey" , "Uncouth type" , "animal" .)