truncated tetrahedron
A truncated tetrahedron is one of the 13 Archimedean solids.
It has 4 regular hexagonal faces, 4 equilateral triangle faces, 12 vertices and 18 edges (of two types). It can be constructed by truncating all 4 vertices of a regular tetrahedron at one third of the original edge length.
The Schlegel diagram of a truncated tetrahedron represents it as a planar graph.
