trisoctahedron

Tris*oc`ta*he"dron, n. Etym: [Gr. octahedron.] (Crystallog.) Defn: A solid of the isometric system bounded by twenty-four equal faces, three corresponding to each face of an octahedron. Tetragonal trisoctahedron, a trisoctahedron each face of which is a quadrilateral; called also trapezohedron and icositetrahedron. -- Trigonal trisoctahedron, a trisoctahedron each face of which is an isosceles triangle.

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