Where does “девяностолетие” come from?

девяностолетие (Russian) comes from Russian ле́то, from Old East Slavic лѣто, from Proto-Slavic lěto, from Proto-Indo-European leh₁tóm.

девяностолетие (Russian): ninety-year period

Definitions

  1. ninety-year period

Ancestry of “девяностолетие”, step by step

девяностолетие traces back through two separate lines of ancestry.

via Russian ле́то

StepLanguageWordMeaning
1Russianле́тоyear; summer, year
2Old East Slavicлѣтоtime
3Proto-Slaviclětosummer; year
4Proto-Indo-Europeanleh₁tóm—

via Russian девяно́сто

StepLanguageWordMeaning
1Russianдевяно́стоninety (90)
Every word from Proto-Indo-European leh₁tóm →Every word from Proto-Slavic lěto →Every word from Old East Slavic лѣто →