Element in rebellion is enjoying acclaim (7)
I believe the answer is:
lionise
'acclaim' is the definition.
(I know that lionise is a more specific form of the action acclaim)
'element in rebellion is enjoying' is the wordplay.
'element in' says the answer is hidden in the clue (I've seen 'elements in' mean this (I've seen this in other clues)).
'LIONISE' is hidden within 'rebellion is enjoying'.
(Other definitions for lionise that I've seen before include "Hero-worship" , "honour" , "Treat as a celebrity - elision (anag)" , "Treat as celebrity - like Leo?" , "'Celebrate, treat as a hero (7)'" .)