Angel spoils her cub (6)
I believe the answer is:
cherub
'angel' is the definition.
(I know that cherub is a type of angel)
'spoils her cub' is the wordplay.
'spoils' indicates an anagram.
'her'+'cub'='hercub'
'hercub' is an anagram of 'CHERUB'.
(Other definitions for cherub that I've seen before include "overweight child" , "Angel shown as a winged child" , "Innocent youngster" , "Lovely child" , "Angel portrayed as a winged child" .)