Where does “пятиугольник” come from?

пятиугольник (Russian) comes from Russian у́гол, from Proto-Slavic ǫgъlъ, from Proto-Balto-Slavic *ángulas, from Proto-Indo-European h₂engulos, from Proto-Indo-European h₂eng- — curve, bend.

пятиугольник (Russian): pentagon

Definitions

  1. pentagon

Ancestry of “пятиугольник”, step by step

пятиугольник traces back through two separate lines of ancestry.

via Russian у́гол

StepLanguageWordMeaning
1Russianу́голangle; corner
2Proto-Slavicǫgъlъcorner, angle
3Proto-Balto-Slavic*ángulas—
4Proto-Indo-Europeanh₂engulosjoint?
5Proto-Indo-Europeanh₂eng-curve, bend

via Russian пять

StepLanguageWordMeaning
1Russianпятьfive; second-person singular imperative...
2Old Church Slavonicпѧтьfive
3Proto-Slavicpętьfive
4Proto-Indo-Europeanpénkʷefive
Every word from Proto-Indo-European h₂eng- →Every word from Proto-Indo-European h₂engulos →Every word from Proto-Balto-Slavic *ángulas →
пятиугольник — Etymology, Origin & Word History | Etymology Explorer