A polygon is a closed, 2-dimensional shape, with edges(sides) are straight lines. The word “polygon” is derived from Greek for “many angles”. The names of the polygons are taken from the Greek number ...A polygon is a closed, 2-dimensional shape, with edges(sides) are straight lines. The word “polygon” is derived from Greek for “many angles”. The names of the polygons are taken from the Greek number prefixes followed by –gon, with only a couple exceptions.