Tease scornfully (4)
I believe the answer is:
mock
'tease scornfully' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for mock that I've seen before include "Taunt" , "Jeer, deride" , "Unreal; ridicule" , "Tease or laugh at" , "Scoff at" .)