<p><strong>Noun</strong></p><ul><li>An area between the extradoses of two adjoining arches, or between the extrados of an arch and a perpendicular through the extrados at the springing line.</li><li>(In a steel-framed building) A panellike area between the head of a window on one level and the sill of a window immediately above.</li><li>(Philately) The decoration occupying the space at the corner of a stamp between the border and an oval or circular central design.</li></ul>