Span"drel (?), n. [From Span.]
1. Arch.
The irregular triangular space between the curve of an arch and the inclosing right angle; or the space between the outer moldings of two contiguous arches and a horizontal line above them, or another arch above and inclosing them.
2.
A narrow mat or passe partout for a picture.
[Cant]
© Webster 1913.