Gladiator ordered to cast off gold headgear (5)
I believe the answer is:
tiara
'headgear' is the definition.
(tiara is a kind of headgear)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for tiara that I've seen before include "Half a crown!" , "Jewelled headpiece" , "Jewelled head-ornament" , "It might go to one's head" , "Jewelled head ornament" .)