Notion inspiring delegates, executives and leaders (4)
I believe the answer is:
idea
'notion' is the definition.
(thesaurus)
'inspiring delegates executives and leaders' is the wordplay.
'leaders' says to take the initial letters.
The initial letters of 'inspiring delegates executives and' is 'IDEA'.
(Other definitions for idea that I've seen before include "Inkling" , "Flash of inspiration?" , "Suggestion" , "Aim" , "Theory" .)