Some polygon names include triangle, quadrilateral, pentagon, hexagon and septagonn. Most polygon names are derived from a Greek word referring to the number of sides a shape has.
A polygon is a closed connection of line segments. Each line segment is called a side. The number of sides is the key piece of information in determining the name of the polygon.
If there are more than five line segments, the name of the polygon comes from the Greek word for the number of sides, followed by "-gon." A polygon with five sides is called a pentagon, and a polygon with six sides is called a hexagon. Similarly, a polygon with seven sides is called a heptagon or septagon, and a polygon with eight sides is called an octagon.
However, the two most familiar polygons do not follow the usual naming conventions. If it has three sides, the polygon is called is a triangle. A four-sided polygon is called a quadrilateral.
As the number of sides increases, the prefixes may be less familiar and sound more interesting. For instance, a polygon with 18 sides is called an octakaidecagon, and a polygon with 10,000 sides is called a myriagon. As the number of sides increases, the polygon looks more and more like a circle.