gyrobifastigium

Noun

gyrobifastigium (plural gyrobifastigia or gyrobifastigiums)

1. A polyhedral solid formed by joining two face-regular triangular prisms along corresponding square faces, giving a quarter-turn to one prism. It is noted for being one of the few regular polyhedra that packs in three dimensions.
   • To elucidate this complex correlation, we carried out detailed Monte Carlo simulations of six convex space-filling polyhedrons, namely, truncated octahedrons, rhombic dodecahedrons, hexagonal prisms, cubes, gyrobifastigiums and triangular prisms.2011 February, Umang Agarwal, Fernando A Escobedo, “Mesophase behaviour of polyhedral particles”, in Nature materials, volume 10
   • They observed hard triangular prisms and hard gyrobifastigia to directly transform into their space-filling crystal, while hard truncated octahedra, rhombic.2012, Amir Haji Akbari Balou, Thermodynamics of the Hard Tetrahedron System (PhD Dissertation in Chemical Engineering, University of Michigan)