metal-plated headband
Archaic military term for a headband reinforced with a metal plate, worn as part of traditional armor.
Warriors in the Sengoku period sometimes wore a metal-plated headband under their helmets.
Compound of 額 (ひたい, 'forehead') and 金 (かね, 'metal'), referring to a metal plate worn on the forehead. The exact historical origin is uncertain.