White stoat fur (6)
I believe the answer is:
ermine
'white stoat fur' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for ermine that I've seen before include "Winter fur of the stoat" , "White fur associated with judges" , "special trimmings" , "Animal with brown fur that turns white in winter" , "White fur of weasel" .)