US composer accepts our bravery (7)
I believe the answer is:
courage
'bravery' is the definition.
(I know that bravery can be written as courage)
'us composer accepts our' is the wordplay.
'us composer' becomes 'cage' (I've seen this in another clue).
'accepts' means one lot of letters goes inside another.
'cage' placed around 'our' is 'COURAGE'.
(Other definitions for courage that I've seen before include "Valour" , "Bottle" , "See 6" , "Grit" , "Bravery, fortitude" .)