hexadecachoron

hexadeca- (“sixteen”) +‎ -choron (“room”), from Ancient Greek ἕξ (héx, “six”), δέκα (déka, “ten”) and χώρος (khṓros, “room”).

hexadecachoron (plural hexadecachorons or hexadecachora)

1. (mathematics) A four-dimensional object analogous to an octahedron, constructed out of sixteen tetrahedra.
   • 2005, V H Satheesh Kumar and P K Suresh, Are We Living in a Higher Dimensional Universe?‎, page 3:

     In a world with four spatial dimensions, for example, we can construct only six regular solids, viz pentatope, tesseract, hexadecachoron, icositetrachoron, hecatonicosachoron and hexacosichoron.

   • 2009, P. Khavari and C. C. Dyer, Aspects of Causality in Parallelisable Implicit Evolution Scheme‎, page 7:

     We have chosen the surfaces of a pentatope (5-cell) as well as a hexadecachoron (16-cell), which are simple standard triangulations of a 3-sphere, shown in figure (7), as our underlying lattices.

   • 2011, Jin Akiyama and Ikuro Sato, The element number of the convex regular polytopes‎, page 271:

     In four dimensions, surprisingly, there are three space-filling convex regular polychora: the tesseract (the hypercube in ℝ⁴), the hexadecachoron, and the icositetrachoron.

• 16-cell