breastplate/ˈbɹɛstˌpleɪt/EtymologyFrom Middle English brestplate, equivalent to breast + plate. Displaced Old English brēostbeorg.breastplate means A piece of armor that covers the chest. Lexicurio rates it Rare gem — a strength score of 79 out of 100.nounA piece of armor that covers the chest.A piece of armor that covers the torso; a cuirass, the breast- (front) and back-plate, taken together as a unit.“He wears a Thracian-style helmet that protects most of his head and face, and a breastplate or "cuirass" covering his back and chest, both made of bronze.”A piece of horse tack designed to prevent the saddle slipping backwards.A piece of silicone in the shape of women's breasts worn by drag queens and other female impersonators to simulate a female body shape.An embroidered square of linen worn on the breast of the Jewish high priest, bearing twelve precious stones, each inscribed with the name of one of the tribes of Israel.