Cowboy headgear (3-6,3)
I believe the answer is:
ten-gallon hat
'cowboy headgear' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for ten-gallon hat that I've seen before include "Item worn by a cowboy" , "Western headgear?" , "Cowboy headgear" , "Texas headgear" , "It features on the head of a cowboy" .)