spandrel - the almost triangular space between one side of the outer curve of an arch, a wall, and the ceiling or framework. Spandrel Wall: a wall built on the curve of an arch, filling in the spandrel. Found on http://www2.shu.ac.uk/sfca/glossary.cfm
1) Spandrel 2) Surface 
spandrel - the almost triangular space between one side of the outer curve of an arch, a wall, and the ceiling or framework. Spandrel Wall: a wall built on the curve of an arch, filling in the spandrel.