Look of contempt (5)
I believe the answer is:
sneer
'look of contempt' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sneer that I've seen before include "Scoff, scorn" , "Curl one's lip" , "Contemptuous gesture" , "Be derisive; Sheridan's Critic" , "Contemptuous or mocking smile" .)