I support province, after reflection (5)
I believe the answer is:
india
'i' is the definition.
(India is I in the NATO phonetic alphabet)
'support province after reflection' is the wordplay.
'support' becomes 'aid' (to aid is to help or support).
'province' becomes 'NI' (short for Northern Ireland, a province of the UK).
'after reflection' says the letters should be written in reverse.
'aid'+'ni'='aidni'
'aidni' backwards is 'INDIA'.
(Other definitions for india that I've seen before include "Populous nation" , "Country of the Ganges" , "A Passage to - (E.M. Forster)" , "Queen Victoria considered it the Jewel in the Crown" , "Cricket team" .)