Back uniform required for worshipper (5)
I believe the answer is:
hindu
'for worshipper' is the definition.
(worshipper of Hindu gods)
'back uniform required' is the wordplay.
'back' becomes 'hind' (synonyms).
'uniform' becomes 'U' (phonetic alphabet: alpha, bravo, charlie etc.).
'required' is a charade indicator (letters next to each other).
'hind'+'u'='HINDU'
(Other definitions for hindu that I've seen before include "Adherent of Indian religion" , "Believer in an Indian religion" , "Central Asian mountain range" , "Eastern believer" , "Adherent of an eastern religion" .)