A pentagonal pyramid
it's a pyramid with 5 sides.
All except the base are always triangles; the shape of the base gives the name to the pyramid; eg a pentagonal pyramid has a pentagon as the base and five triangular faces; a triangular pyramid has three triangular faces and also has a triangle for the base.
A square pyramid.
pentagonal pyramid
A solid figure with a pentagon as its base and triangular faces is called a pentagonal prism. In this 3D shape, the two pentagonal bases are parallel and connected by five rectangular lateral faces. However, if you specifically mean a solid with a pentagonal base and triangular faces that converge at a single point, then it is known as a pentagonal pyramid.
A pyramid with an irregular pentagon base.
pyramid
pentagonal pyramid
Triangular Pyrimid
It is a pyramid
That would be a triangular pyramid.
Six - five triangular faces above the base, and then the pentagon base itself counts as a face.