You take a look at what 2-D shape the face is, and then that's the name of the face.
Icosahedron
If the faces are flat, it's a line.
Isosceles TetrahedronA solid with four faces is a tetrahedron. Each of the faces is a triangle. If all the triangles are congruent, you have an isosceles tetrahedron.
a cylinder a cylinder
A solid figure with twenty faces is called an Icosahedron.
Icosahedron
A vertex is the name of a corner on a solid where three or more faces meet (plural = vertices).
A cube has six square faces.
If the faces are flat, it's a line.
The solid with 12 equal faces is a dodecahedron. A dodecahedron has 12 equal pentagon surfaces.
an edge
triangular prism
a triangular prism.
Isosceles TetrahedronA solid with four faces is a tetrahedron. Each of the faces is a triangle. If all the triangles are congruent, you have an isosceles tetrahedron.
They have compound names which use Greek prefices for the number of faces, and the suffix "hedron".So, an octahedron would be a solid with 8 faces.
A cone
Tetrahedron