In geometry, a

**heptadecagon**is a seventeen-sided polygon.

See also Carl Friedrich Gauss and Ruler and compass constructions.

You can see how to construct regular 17-gon geometrically at

http://www.showmath.co.kr/const/polygon/rpoly17.html

And you can see algebraic aspect (by Gauss) in this book :

'Famous Problems and Other Monographs' by F.Klein et al.