English

Noun

octangle ‎(plural octangles)

1. A geometric figure with eight corners, an octagon.
   • 1853 May, Weddle, Thomas, “On certain geometrical relations between a surface of the second degree and a tetrahedron whose edges touch the surface”, in The Cambridge and Dublin Mathematical Journal, volume 8, page 130:

     The angles of any two of the tetrahedra ABCD, A′B′C′D′, and OO′O″O‴ form the angles of a complete syngrammatic octangle whose syngrammatic points are the angles of the other tetrahedron […]