Where does “тридцатиугольник” come from?

тридцатиугольник (Russian) comes from Russian три́дцать, from Russian три, from Macedonian трие, from Proto-Slavic trьje, from Proto-Balto-Slavic tríjes, from Proto-Indo-European *tréyes.

тридцатиугольник (Russian): triacontagon

Definitions

  1. triacontagon

Ancestry of “тридцатиугольник”, step by step

тридцатиугольник traces back through two separate lines of ancestry.

via Russian три́дцать

StepLanguageWordMeaning
1Russianтри́дцатьthirty (30)
2Russianтриthree; second-person singular imperative...
3Macedonianтриеto rub
4Proto-Slavictrьjethree
5Proto-Balto-Slavictríjesthree
6Proto-Indo-European*tréyes—

via Russian у́гол

StepLanguageWordMeaning
1Russianу́голangle; corner
2Proto-Slavicǫgъlъcorner, angle
3Proto-Balto-Slavic*ángulas—
4Proto-Indo-Europeanh₂engulosjoint?
5Proto-Indo-Europeanh₂eng-curve, bend
Every word from Proto-Indo-European *tréyes →Every word from Proto-Balto-Slavic tríjes →Every word from Proto-Slavic trьje →