In dictionaries:
regular tetrahedron
Four equilateral triangles as sides.
truncated tetrahedron
(geometry) A convex polyhedron, with four triangular and four hexagonal faces, that is an Archimedean solid and can be constructed by truncating a regular tetrahedron at each vertex by one-third the length of each adjoining edge.
Tetrahedron in Bottrop
The (German: Bottrop Tetraeder or officially Haldenereignis Emscherblick) a walkable steel structure in the form of a tetrahedron with a side length of 60m, resting on four 9m tall concrete pillars.
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