Survive, being revealed before final (7)
I believe the answer is:
outlast
'survive' is the definition.
('outlast' can be a synonym of 'survive')
'revealed before final' is the wordplay.
'revealed' becomes 'out' (I've seen this in other clues).
'before' means one lot of letters go next to another.
'final' becomes 'last' ('last' can be a synonym of 'final').
'out'+'last'='OUTLAST'
'being' is the link.
(Other definitions for outlast that I've seen before include "Survive beyond" , "Live longer than" , "Persist longer than" , "Go on longer than" , "carry on after all others" .)