Where does “poligonal” come from?

poligonal (Portuguese) comes from Portuguese polígono, from Ancient Greek πολύγωνον, from Ancient Greek πολύγωνος, from Ancient Greek γωνία, from Ancient Greek γόνυ, from Proto-Hellenic gónu, from Proto-Indo-European ǵónu — knee.

poligonal (Portuguese): polygonal

Definitions

polygonal

Ancestry of “poligonal”, step by step

Step	Language	Word	Meaning
1	Portuguese	polígono	polygon
2	Ancient Greek	πολύγωνον	polygon
3	Ancient Greek	πολύγωνος	polygonal, many-angled
4	Ancient Greek	γωνία	corner, angle; joiner's square; cornerstone
5	Ancient Greek	γόνυ	knee
6	Proto-Hellenic	gónu	knee
7	Proto-Indo-European	ǵónu	knee

Every word from Proto-Indo-European ǵónu →Every word from Proto-Hellenic gónu →Every word from Ancient Greek γόνυ →