spandrel

Meaning

Noun

• The space (often more or less triangular) between the outer curve of an arch (the extrados) and a straight-sided figure that bounds it; the space between two contiguous arches and a straight feature above them.
• Horizontal member between the windows of successive storeys of a tall building.
• The triangular space under a stair; the material that fills the space.
• An oriental rug having a pattern of arches; the design in the corners of such a rug, especially in a prayer rug.
• A phenotypic characteristic that evolved as a side effect of an adaptation in response to evolutionary pressure.

Origin

• From a diminutive of Anglo-Norman spaundre, of uncertain origin, perhaps from Old French espandre ("to expand, extend, spread"). In the field of biology first used by Stephen Jay Gould and Richard Lewontin.{{cite-journal
• |title=The spandrels of San Marco and the Panglossian paradigm: a critique of the adaptationist programme
• |date=1979-09-21
• |work=Proceedings of the Royal Society of London. Series B. Biological Sciences
• |doi=10.1098/rspb.1979.0086
• |author=S. J. Gould
• |authorlink=Stephen Jay Gould
• |author2=R. C. Lewontin
• |authorlink2=Richard Lewontin
• |url=https://cbs.asu.edu/sites/default/files/PDFS/GouldLewontinSpandrels.pdf