Abrupt or ungracious rejection (6)
I believe the answer is:
rebuff
'abrupt or ungracious rejection' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for rebuff that I've seen before include "Blunt rejection" , "Reject in an ungrateful manner" , "Refuse" , "Spurn, snub" , "Ungracious rejection of a friendly approach" .)