an isosagon is a regular 20 sided polygon.
isosagon * * * * * icosagon.
An isosagon is a polygon that has 20 sides. The term combines "iso," meaning equal, and "agon," meaning angle or corner, indicating that all sides and angles are equal in a regular isosagon. This shape is part of the family of polygons, which includes triangles, quadrilaterals, and many others.