Which part of a suit of armour (armor) protects the torso?

A cuirass French: cuirasse, Latin: coriaceus) is a piece of armour that covers the torso, formed of one or more pieces of metal or other rigid material. The word probably originates from the original material, leather, from the French cuirace and Latin word coriacea. The use of the term "cuirass" generally refers to both the breastplate and the backplate pieces; whereas a breastplate only protects the front, a cuirass protects both the front and the back of the wearer.