City rebel became a star (9)
I believe the answer is:
celebrity
'a star' is the definition.
(star can mean a famous person)
'city rebel became' is the wordplay.
'became' indicates anagramming the letters (I've seen 'become' mean this).
'city'+'rebel'='cityrebel'
'cityrebel' is an anagram of 'CELEBRITY'.
(Other definitions for celebrity that I've seen before include "Star" , "name" , "Famous person seen in rebel city" , "target of paparazzo?" , "Fame" .)