diangle

From di- +‎ angle.

• IPA^(key): /ˈdaɪˌæŋɡəl/

diangle (plural diangles)

1. A digon or bigon; a two-sided shape.
   • 1853, “The Science of Medicine”, in The Journal of Psychological Medicine and Mental Pathology‎, page 241:

     The diangle ABCD indicates the entire duration of life, A and C being its commencement and its termination.

   • 1949, Arnold Sommerfeld, Ernst G. Strauss, transl., Partial Differential Equations in Physics‎, volume 1, Academic Press, page 319:

     Now the wedge 1,2 is mapped into the exterior of the circular diangle C,S₁,1,O,2,S₂,C; both regions are indicated by a shading of the boundary. We now seek the images of the reflected wedges.

   • 1969, Siberian Mathematical Journal‎, Kluwer/Plenum Publishers, page 107:

     Let B be a region of F bounded by a closed polygon comprised of segments of geodesics of surface F, and let h_n be a sequence of nondegenerate diangles of region B whose sides are geodesics of region B and which converge to diangle h_n.

• digon, bigon, biangle