The cuboctahedron is a uniform polyhedron bounded by 6 squares and 8 triangles. It is edge-uniform, and its two kinds of faces alternate around each vertex, so it is also a quasi-regular polyhedron. It may be constructed by truncating a cube or an octahedron at the midpoints of its edges (this process is known as rectification).
In order to be able to identify the cuboctahedron in various projections of 4D objects, it is useful to know how it appears from various viewpoints. The following are some of the commonly-encountered views:
Parallel projection centered on a square face.
Parallel projection centered on a triangular face.
The Cartesian coordinates of the cuboctahedron, centered on the origin and having edge length 2, are all permutations of coordinates and changes of sign of:
- (0, √2, √2)
The cuboctahedron occurs as cells in a variety of 4D uniform polytopes:
- The cantellated 5-cell;
- The runcitruncated 5-cell;
- The rectified tesseract;
- The runcitruncated tesseract;
- The rectified 24-cell;
- The cantellated 24-cell;
- The runcitruncated 120-cell;
- The cantellated 600-cell.
Some CRF polychora also contain cuboctahedral cells, including (but not limited to):