What is the name of the polyhedron formed by slicing a pyramid with a plane parallel to its base?

The name of the polyhedron formed by slicing a pyramid with a plane that is parallel to its base is known as a frustum of a pyramid. When this slicing occurs, the result is a truncated pyramid, where the original apex of the pyramid is removed, and the remaining structure retains the shape of the base at the cut. This generates two parallel bases, one of which is the original base of the pyramid, and the other is the new smaller polygon formed by the intersection with the slicing plane.

A frustum has the characteristic of having different-sized bases, which is a defining feature that distinguishes it from other polyhedra such as prisms and cylinders. In a prism, the two bases are identical and the sides are parallel; in a cylinder, the bases are also identical but circular. Meanwhile, a hexagon is simply a six-sided polygon and does not convey any information about three-dimensional shapes or the concept of slicing a pyramid. Thus, the correct nomenclature for the polyhedron created when slicing a pyramid parallel to its base is indeed the frustum of a pyramid.