It is a face of the polyhedron
The flat surfaces of all polyhedra are called faces and a rectangular prism is simply one kind of polyhedron.
A sphere is not a polyhedron because it has no edges, no vertices and no flat faces The word 'polyhedron' means many faces.
A flat surface generally refers to a horizontal surface and is referred to as the plane.
One flat surface is a table. Many flat surfaces are facets.
It is a face of the polyhedron
It is called the surface area.
a base
A face.
Each surface of a polyhedron is called a face.
faces every polyhedron has one
cross section
faces
It is a polyhedron.
Its surface, would you believe!
Face
Its called a net.