Girl eating cheese is angel (7)
I believe the answer is:
gabriel
'is angel' is the definition.
(I've seen this before)
'girl eating cheese' is the wordplay.
'girl' becomes 'gal' (synonyms).
'eating' means one lot of letters goes inside another.
'cheese' becomes 'brie' (Brie is an example).
'gal' going around 'brie' is 'GABRIEL'.
(Other definitions for gabriel that I've seen before include "Angel of Annunciation" , "Boy" , "Archangel who plays the trumpet" , "Dante - Rossetti, nineteenth century English poet/painter" , "musician" .)