Polygons with 3, 4, 5, 6, 7, 8, 9, 10, and 12 sides all have special names like triangle or hexagon. All other polygons can be called n-gons. You can think of n-gon as meaning "any" number of sides, or whatever number of sides your current polygon has. The polygon shown with the question has 13 sides, so it can be called a n-gon or a 13-gon.
