Savage female promises to accept returned Apple component (9)
I believe the answer is:
ferocious
'savage' is the definition.
(synonyms)
'female promises to accept returned apple component' is the wordplay.
'female' becomes 'f' (common abbreviation).
'promises' becomes 'ious' (IOU's, promises to pay a debt).
'to accept' indicates putting letters inside.
'returned' says the letters should be written in reverse.
'apple component' becomes 'core' (part of an apple).
'core' backwards is 'eroc'.
'f'+'ious'='fious'
'fious' going around 'eroc' is 'FEROCIOUS'.
(Other definitions for ferocious that I've seen before include "Savagely fierce" , "potentially harmful" , "very intense" , "Savage as a wild beast" , "Savagely cruel" .)