White-coated weasel (6)
I believe the answer is:
ermine
'white-coated weasel' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ermine that I've seen before include "special trimmings" , "Animal with brown fur that turns white in winter" , "Stoat in its winter coat" , "garb for nobility" , "White fur of stoat" .)