In geometry, a bitruncation is an operation on regular polytopes.
Bitruncated regular polytopes can be represented by an extended Schläfli symbol notation t1,2{p,q,...} or 2t{p,q,...}.
For a regular 4-polytope, a bitruncated form is a dual-symmetric operator.
An interesting result of this operation is that self-dual 4-polytope {p,q,p} (and honeycombs) remain cell-transitive after bitruncation.
There are 5 such forms corresponding to the five truncated regular polyhedra: t{q,p}.