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