Provincial half of army behind endless abuse (7)
I believe the answer is:
insular
'provincial' is the definition.
('insular' can be similar in meaning to 'provincial')
'half of army behind endless abuse' is the wordplay.
'half of army' becomes 'ar' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'behind' means one lot of letters go next to another.
'endless' means to remove the last letter.
'abuse' becomes 'insult' ('insult' can be a synonym of 'abuse').
'insult' with its final letter taken off is 'insul'.
'ar' after 'insul' is 'INSULAR'.
(Other definitions for insular that I've seen before include "Aloof - prejudiced" , "Lacking contact with other people" , "Circumscribed" , "Surrounded by water - narrow - prejudiced" , "Lacking contact with others" .)