Exclude its coarse form (9)
I believe the answer is:
ostracise
'exclude' is the definition.
(I know that ostracise is a type of exclude)
'its coarse form' is the wordplay.
'form' indicates an anagram.
'its'+'coarse'='itscoarse'
'itscoarse' with letters rearranged gives 'OSTRACISE'.
(Other definitions for ostracise that I've seen before include "Cast out, blackball" , "exile" , "Blackball, send to Coventry" , "Banish, blackball" , "Banish from group" .)