Stain ruined shiny material (5)
I believe the answer is:
satin
'shiny material' is the definition.
'stain ruined' is the wordplay.
'ruined' indicates anagramming the letters.
'stain' with letters rearranged gives 'SATIN'.
(Other definitions for satin that I've seen before include "Smooth and silky" , "Stain on silky cloth" , "Saint (anag.)" , "covered with?" , "Glossy textile" .)