Angel-lights

Angel-lights, in architecture, are the upper panes of glass or "lights'" in a curved window frame, next to the springing; probably a corruption of the word angle lights, as they are nearly triangular.

References

•  This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed (1911). "Angel-lights". Encyclopædia Britannica (11th ed.). Cambridge University Press.