Geom. and Cryst. [f. TRIS- + OCTAHEDRON.] A solid figure having 24 faces, every three of which correspond to one face of an octahedron: either with triangular faces (= triakisoctahedron), or with trapezoidal faces (= deltohedron, icositetrahedron, or trapesohedron). Hence Trisoctahedral a., pertaining to or having the form of a trisoctahedron.
1847. Webster (citing Dana), Trisoctahedron.
1891. Cent. Dict., Trisoctahedral.
