Jade

A hard, usually green stone that can be polished and carved, often used in jewelry and art. It is especially important in East Asian cultures.

From French “jade,” from Spanish “piedra de ijada,” meaning “stone of the flank,” because it was once believed to cure kidney and side pains. The Spanish phrase was shortened and blended into a single word as it moved into other languages. Over time, the medical belief faded, but the stone kept its name.