polyhedron
An irregular polyhedron if it has plane faces. If not, then there usually will not be a name for it.
3d shapes with plane faces are called polyhedra (singular = polyhedron). The minimum number of vertices is 4, there is no maximum.
a polyhedron * * * * * That is only if it is bounded by plane faces. A sphere, for example, is a three dimensional shape but is not a polyhedron: it is a solid shape.
A polyhedron is a solid figure with many plane faces, usually greater than six. A polyhedron that has 7 faces is called a heptahedron.
Any polyhedron.
An icosahedron is a polyhedron has 20 faces, and is a 3D shape.
polyhedron
None. A polyhedron is 3 dimensional and you cannot make a 2 dimensional shape out of 3D shapes.
Any polyhedron.
An 8-faced 3D shape is called an octahedron. It is a polyhedron with eight triangular faces, 12 edges, and six vertices.
It cannot be a polyhedron nor any "normal" 3d shape.
The faces in a 3-D shape (polyhedron, for example) are bordered by edges.
An irregular polyhedron if it has plane faces. If not, then there usually will not be a name for it.
3d shapes with plane faces are called polyhedra (singular = polyhedron). The minimum number of vertices is 4, there is no maximum.
a polyhedron * * * * * That is only if it is bounded by plane faces. A sphere, for example, is a three dimensional shape but is not a polyhedron: it is a solid shape.
A tetradecachedron is a polyhedron, also known as a 14-sided polyhedron or 14-faced polyhedron. It is a convex solid with 14 faces, 24 edges, and 14 vertices. The term "tetradecachedron" can refer to any 14-faced polyhedron, not necessarily a specific shape.