A polygon is identified based on the number of its sides and vertices. Polygons are made of straight lines, called edges or sides, that meet in corners to form a closed circuit. The least number of sides needed to form a closed loop is three. A three-sided polygon is called a triangle. The list of common polygons includes quadrilateral, pentagon, hexagon, heptagon, octagon, nonagon and decagon.
The catalog of shapes also includes the 11-sided polygon called the hendecagon, or undecagon, and the 12-sided polygon named dodecagon. MathsIsFun provides a list of polygons with up to 10 raised to the 100th power sides, which is called a googolgon. MathsIsFun also has a table of prefixes and suffixes to use in naming polygons. Figures with between 20 and 29 sides have names starting with the prefix “icosi-.“ A 22-sided polygon is called an icosidigon, where the suffix “-digon” is attached to denote that the digit in the ones place is two.
Not all polygons have accepted names or even proposed names, which is why those with 13 or more sides are frequently referred to using the n-gon form, where n is the number of sides. Therefore, a 27-sided figure is called a 27-gon.