Where does “sexagon” come from?

sexagon (English) comes from English -gon, from Ancient Greek γωνία, from Ancient Greek γόνυ, from Proto-Hellenic gónu, from Proto-Indo-European ǵónu — knee.

Ancestry of “sexagon”, step by step

StepLanguageWordMeaning
1English-gonForms the names of plane figures containing a...
2Ancient Greekγωνίαcorner, angle; joiner's square; cornerstone
3Ancient Greekγόνυknee
4Proto-Hellenicgónuknee
5Proto-Indo-Europeanǵónuknee
Every word from Proto-Indo-European ǵónu →Every word from Proto-Hellenic gónu →Every word from Ancient Greek γόνυ →