Military fur hat (5)
I believe the answer is:
busby
'military fur hat' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for busby that I've seen before include "Bearskin hat" , "Mil. bearskin (colloq.)" , "Guardsman's helmet" , "Military fur hat" , "Hussar's hat" .)