Bad stain in cloth (5)
I believe the answer is:
satin
'cloth' is the definition.
(satin is a kind of cloth)
'bad stain' is the wordplay.
'bad' is an anagram indicator.
'stain' anagrammed gives 'SATIN'.
'in' is the link.
(Other definitions for satin that I've seen before include "Smooth glossy fabric" , "Silk fabric" , "Stain on shiny cloth" , "Rich cloth" , "Smooth and silky" .)