Not forthcoming (5)
I believe the answer is:
cagey
'not forthcoming' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for cagey that I've seen before include "not open" , "reluctant to give information" , "guarded" , "Secretive, cautious about giving information" , "Keeping things to oneself" .)