spandrel

(span′drəl)

noun

either of the triangular spaces between the exterior curve of an arch and a rectangular frame or mold enclosing it
any of the spaces between a series of arches and a straight cornice running above them

Origin: ME spaundrell, dim. of Anglo-Fr spaundre < OFr espandre, to expand < L expandere, expand

See spandrel in American Heritage Dictionary 4

also span·dril

noun

The roughly triangular space between the left or right exterior curve of an arch and the rectangular framework surrounding it.
The space between two arches and a horizontal molding or cornice above them.

Origin:

Origin: Middle English spaundrell

Origin: , probably from spandre, space between supporting timbers

Origin: , from Anglo-Norman spaundre

Origin: , from spandre, to spread out

Origin: , from Latin expandere; see expand

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