A pyramid seems to fit the description.
For every polyhedron, there is a dual which is a polyhedron that has:a face where the first had a vertex,a vertex where the first had a face,the same number of edges.A self-dual polyhedron is a polyhedron whose dual is the same shape.All pyramids, for example, are self-dual.
It may be called an apex, but that is really only appropriate for a simple convex polyhedron.
The vertex is a point of polygon or polyhedra that is formed by 2 lines or 3 edges on a polyhedron.
Vertex
A pyramid has a polygonal base with all other sides being triangles. As the Egyptians famously demonstrated, a common pyramid has a square base with four triangles meeting at a vertex, but any polygon - regular or irregular - can be used as the base of such a polyhedron.
pyramid An pyramid is a geometric solid of the shape made famous by the royal tombs of ancient Egypt. It is a solid whose base is a polygon and whose lateral faces are triangles with a common vertex
A polyhedron of which one face is a square, and the other faces are triangles with a common vertex.
A pyramid
A polyhedron of which one face is a polygon of any number of sides, and the other faces are triangles with a common vertex.
A pyramid seems to fit the description.
A pyramid fits the given description
a pyramid
Assuming you are talking about two triangles, "meet at a side" means they have a shared side. This side has two vertices, each of which is a vertex of both triangles. However, if the triangles only share one vertex, so that the tip of one triangle touches the tip of the other, they will have no side in common.
For every polyhedron, there is a dual which is a polyhedron that has:a face where the first had a vertex,a vertex where the first had a face,the same number of edges.A self-dual polyhedron is a polyhedron whose dual is the same shape.All pyramids, for example, are self-dual.
The given description fits that of a triangular based pyramid which has 4 faces, 6 edges and 4 vertices
That's a "vertex" of polyhedron or of her cousin tipi.