chanfron

Barding (also spelled bard or barb) is armour for horses. During the late Middle Ages as armour protection for knights became more effective, their mounts became targets. This tactic was effective for the English at the Battle of Crécy in the fourteenth century where archers shot horses and heavy infantry killed the French knights after they dismounted. Barding developed as a response to such events.
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chanfron
n : medieval plate armor to protect a horse's head [syn: chamfron, testiere, frontstall]

Noun
1. medieval plate armor to protect a horse's head
(synonym) chamfron, testiere, frontstall, front-stall
(hypernym) armor plate, armour plate, armor plating, plate armor, plate armour

armour for a horse's head