Plumed headgear (5)
I believe the answer is:
shako
'plumed headgear' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for shako that I've seen before include "military headdress" , "Old headgear" , "One covering for military head" , "old military item" , "Ceremonial hat" .)