Where does “тридцатилетие” come from?

тридцатилетие (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.

тридцатилетие (Russian): thirty-year period

Definitions

  1. thirty-year period

Ancestry of “тридцатилетие”, step by step

тридцатилетие 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 ле́то

StepLanguageWordMeaning
1Russianле́тоyear; summer, year
2Old East Slavicлѣтоtime
3Proto-Slaviclětosummer; year
4Proto-Indo-Europeanleh₁tóm—
Every word from Proto-Indo-European *tréyes →Every word from Proto-Balto-Slavic tríjes →Every word from Proto-Slavic trьje →