In some ridicule, stumped by Joker (6)
I believe the answer is:
jester
'joker' is the definition.
(thesaurus)
'in some ridicule stumped' is the wordplay.
'in' is an insertion indicator.
'some ridicule' becomes 'jeer' (jeer is a kind of ridicule).
'stumped' becomes 'st' (I've seen this in other clues).
'jeer' going around 'st' is 'JESTER'.
'by' acts as a link.
(Other definitions for jester that I've seen before include "Comic" , "Court clown" , "Clown employed to entertain a ruler" , "Professional joker" , "Yorick" .)