An adze is an old-fashioned kind of ax or hatchet, used to carve wood. The very oldest adze blades were made of stone.
Way back in ancient Egypt, an adze's stone blade was tied to its wooden handle. When metal blades replaced the stone ones, they were usually fitted into notches in the handle of the adze. These ax-like tools are still used today — their curved shape, with blades perpendicular to the handles, lends itself well to woodworking.