Finale on stage for celebrity (6)
I believe the answer is:
legend
'for celebrity' is the definition.
(both can mean a renowned person)
'finale on stage' is the wordplay.
'finale' becomes 'end' (the end of a story or show).
'on' says to put letters next to each other.
'stage' becomes 'leg' (a leg is a stage of a competition).
'end' put after 'leg' is 'LEGEND'.
(Other definitions for legend that I've seen before include "Celebrity" , "Person who has become famous" , "King Arthur" , "The story of Achilles, say" , "Traditional story - inscription" .)