In mathematics, a **hexadecagon** (sometimes called a hexakaidecagon) or 16-gon is a sixteen-sided polygon.

3 = triangle or trigon

4 = quadrilateral or tetragon

5 = pentagon

6 = hexagon

7 = heptagon

8 =octagon

9 = enneagon

10 = decagon

11 = hendecagon

12 = dodecagon

13 = triskaidecagon or tridecagon

14 = tetrakaidecagon or tetradecagon

15 = pentadecagon

**16 = hexadecagon**

17 = heptadecagon

18 = octdecagon

19 = enneadecagon

20 = icosagon

Hexadecagon has 16 side.