Where does “двадцатиодноугольник” come from?

двадцатиодноугольник (Russian) comes from Russian двадца́ть, from Russian два, from Old East Slavic дъва, from Proto-Slavic dъva, from Proto-Balto-Slavic duwō, from Proto-Indo-European dwóh₁ — two.

двадцатиодноугольник (Russian): icosihenagon

Definitions

  1. icosihenagon

Ancestry of “двадцатиодноугольник”, step by step

двадцатиодноугольник traces back through two separate lines of ancestry.

via Russian двадца́ть

StepLanguageWordMeaning
1Russianдвадца́тьtwenty (20)
2Russianдваtwo
3Old East Slavicдъваtwo
4Proto-Slavicdъvatwo
5Proto-Balto-Slavicduwōtwo
6Proto-Indo-Europeandwóh₁two

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 dwóh₁ →Every word from Proto-Balto-Slavic duwō →Every word from Proto-Slavic dъva →