spandrel
spand·rel
noun
1.
an approximately triangular surface area between two adjacent arches and the horizontal plane above them
Origin
From a diminutive in -el of Anglo-Norman spaundre, of uncertain origin, perhaps from Old French espandre (“to expand, extend, spread”). More at spawn, expand. In the field of biology first used by Stephen Jay Gould and Richard Lewontin.
Related words
Broader terms
WordNet 2.1 (Princeton University). Wiktionary (CC BY-SA). WordNet 2.1 Copyright Princeton University. All rights reserved. Wiktionary content is available under the Creative Commons Attribution-ShareAlike Licence.