There are generic geometric names for the most common polyhedra. The 5 Platonic solids are called a tetrahedron, hexahedron, octahedron, dodecahedron and icosahedron with 4, 6, 8, 12, and 20 sides respectively. The regular hexahedron is a cube.

An octadecagram is an 18-sided star polygon, represented by symbol {18/n}. There are two regular star polygons: {18/5} and {18/7}, using the same points, but connecting every fifth or seventh points.

In geometry, a polygon is traditionally a plane figure that is bounded by a finite chain of straight line segments closing in a loop to form a closed chain. These segments are called its edges or sides, and the points where two of the edges meet are the polygon's vertices (singular: vertex) or …

Everything you need to know about 3D shapes! This free guide covers every 3d shape including 3d shape names, definitions, and 3d shape drawings. Plus you can download a free pdf 3d shapes chart.

Apr 3, 2025 · Weisstein, Eric W. "Octadecagon." From MathWorld --A Wolfram Web Resource. https://mathworld.wolfram.com/Octadecagon.html. An 18-sided polygon, sometimes also …

Here you will learn about 3D shape names, including types of polyhedra (prisms, pyramids, platonic solids, irregular), non-polyhedra (cones, cylinders, spheres, hemispheres) and compound 3D shapes. Students will first learn about 3D shape names as part of geometry in 1 st grade.

Beyond three dimensions, one can explore four dimensional shapes like the tesseract or the grand antiprism. If you would like to learn more about polyhedra and other geometric figures, check out these links:

Polygons are geometric figures of the 2D plane made up of a series of closed segments. The number of segments (called sides or edges) is equal to the number of vertices (or corners) used to define the geometric shape of the polygon.

Information about the Octadecagons, polygons with 18 sides.

An 18 sided shape is called an octadecagon (octa meaning 8 and decagon meaning 10) A 19 sided shape is called an enneadecagon (pronounced en-ee-deck-uh-gon) A 20 sided shape is called an icsoagon. All of these shapes are from the polygon family.