Great icosagram

The great icosagram, or gig, is a non-convex polygon with 20 sides. It's created by taking the eighth stellation of an icosagon. A regular icosagram has equal sides and equal angles.

It is one of three regular 20-sided star polygons, the other two being the small icosagram and the icosagram.

It is the uniform quasitruncation of the decagon.