The stapes is the stirrup-shaped small bone or ossicle in the middle ear which is attached through the incudostapedial joint to the incus laterally and to the fenestra ovalis, the "oval window", medially. The oval window is adjacent to the vestibule of the inner ear. The stapes is the smallest and lightest bone in the human body. It was described by the professor Giovanni Filippo Ingrassia in 1546 at the University of Naples.