Pariah is not in shed (7)
I believe the answer is:
outcast
'pariah' is the definition.
(synonyms)
'not in shed' is the wordplay.
'not in' becomes 'out' ('out' is the opposite to 'in').
'shed' becomes 'cast' (shed can mean to discard or cast off).
'out'+'cast'='OUTCAST'
'is' is the link.
(Other definitions for outcast that I've seen before include "In one of the islands, Joseph wrote" , "Social pariah or reject" , "one sent to Coventry" , "untouchable" , "One excluded from group" .)