What Is a 25-Sided Polygon Called?

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A polygon with 25 sides is called a icosikaipentagon. Polygon names are constructed according to the tens unit and the single digit unit.

For instance, “icosi” is the tens digit, which means “20.” “Kai” is essentially a conjunction, as it is the Greek word for “and.” “Penta” represents the ones digit, meaning “five,” and “gon” is added to every polygon to distinguish it as a name for a shape.

Names can be constructed for polygons with even more sides. For instance, a polygon with 743 sides begins with the ones digit “hepta” for seven, followed by “hecta” to indicate “100.” “Tetraconta” is for “40,” followed by “kai.” “Tri” is for “three,” and “gon” is added to the end for the shape’s name. Therefore, a polygon with 743 sides is called a heptahectatetracontakaitrigon.