cuisse n : armor plate that protects the thigh
Cuisses are a form of medieval armor worn to protect the thigh. The word is the plural of the French word cuisse meaning 'thigh'. While the skirt of a maille shirt or tassets of a cuirass could protect the upper legs from above, a thrust from below could avoid these defenses. Thus, cuisses were worn on the thighs to protect from such blows. Padded Cuisses made in a similar way to a Gambeson were commonly worn by knights in the 12th and 13th centuries, usually over Chausses and may have had Poleyns directly attached to them.
Cuisses could also be made of studded or splinted leather, but by the Late Middle Ages they were typically a form plate armour.