an edge or in more simpler term "side"
If the faces are flat, it's a line.
Icosahedron
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
You take a look at what 2-D shape the face is, and then that's the name of the face.
an edge
an edge
The edge.
An edge.
If the faces are flat, it's a line.
A vertex is the name of a corner on a solid where three or more faces meet (plural = vertices).
The place where two faces of a solid meet is called an "edge." In geometry, an edge is a line segment that connects two vertices of a polygon or polyhedron. It is an essential element in defining the shape and structure of three-dimensional objects.
a vortex
The corner of a solid where two faces meet is called a "vertex." In three-dimensional geometry, a vertex is a point where edges converge, and it is one of the key elements in defining the shape of a solid. For example, a cube has eight vertices.
an edge
That is a vertex.
A corner