oeil-de-boeuf window, in architecture, a small circular or oval window, usually resembling a wheel, with glazing bars (bars framing the panes of glass) as spokes radiating outward from an empty hub, or circular centre. In French, oeil-de-boeuf means “eye of the steer,” and, in the French chateau of Versailles, erected for Louis XIV between 1661 and 1708, there is a small antechamber called the oeil-de-boeuf room, which is lighted by such a small, round window. This type of window is also frequently featured in the Jacobean manor houses of 17th-century England.