Great octadecagram

The great octadecagram, or godge, is a non-convex polygon with 18 sides. It's created by taking the sixth stellation of an octadecagon. A regular great octadecagram has equal sides and equal angles.

It is one of two regular 18-sided star polygons, the other being the great octadecagram.

It is the uniform quasitruncation of the enneagram.