Fur trimming on royal robes (6)
I believe the answer is:
ermine
'fur trimming on royal robes' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for ermine that I've seen before include "garb for nobility" , "White fur associated with judges" , "In mere strange fur" , "White-coated stoat" , "Stoat in northern regions" .)