Derision from a heartless jester (4)
I believe the answer is:
jeer
'derision' is the definition.
(I know that jeer is a type of derision)
'a heartless jester' is the wordplay.
'a heartless' says to hollow out the word (remove centre letters).
'jester' with its centre taken out is 'JEER'.
'from' acts as a link.
(Other definitions for jeer that I've seen before include "Ridicule noisily" , "Taunt" , "Call out derisively" , "Catcall" , "Barrack" .)