spand

Spand, also known as spandrel, is an architectural term that describes the space between two arches and a horizontal line that spans across their tops. This triangular or trapezoidal area is often filled in with decorative elements or left as a void. The term can also refer to a similar space created by an arch and a rectangular frame. In Gothic architecture, spandrels were frequently ornamented with carvings, tracery, or painted designs, adding visual interest and complexity to vaulted ceilings and arcades. The term has also been adopted in other fields, such as engineering, to describe similar triangular spaces in structural frameworks. In some contexts, "spandrel" can also refer to the area between the curve of a stair and the outer wall, or the space above a doorway or window. The aesthetic and structural role of spandrels varies greatly depending on the architectural style and the specific application.