Fabric to tear asunder or scratch (8)
I believe the answer is:
lacerate
'scratch' is the definition.
(thesaurus)
'fabric to tear asunder' is the wordplay.
'fabric' becomes 'lace' (lace is a kind of fabric).
'to' means one lot of letters go next to another.
'asunder' indicates anagramming the letters (I've seen this in other clues).
'tear' anagrammed gives 'rate'.
'lace'+'rate'='LACERATE'
'or' acts as a link.
(Other definitions for lacerate that I've seen before include "Tear roughly, cut jaggedly" , "Tear or cut (flesh) deeply" , "Clare ate (anag)" , "Slash" , "Deeply cut (flesh, skin)" .)