The legend of Jeremy Thorpe (4)
I believe the answer is:
myth
'the legend' is the definition.
(thesaurus)
'of jeremy thorpe' is the wordplay.
'of' indicates a hidden word.
'MYTH' can be found hidden inside 'jeremy thorpe'.
(Other definitions for myth that I've seen before include "Common false belief" , "Story of old gods" , "Invention" , "Illusion" , "Delusion" .)