Derisive reactions (6)
I believe the answer is:
sneers
'derisive reactions' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for sneers that I've seen before include "Jeers, derides" , "Expresses cynical contempt" , "Shows scorn" , "Smiles contemptuously" , "Shows contempt by scornful expression" .)