Where does “десятилетний” come from?

десятилетний (Russian) comes from Russian де́сять, from Old Church Slavonic десѧть, from Proto-Slavic desętь, from Proto-Balto-Slavic *déśimt, from Proto-Indo-European déḱm̥t — ten.

десятилетний (Russian): ten-year; decennial; ten-year-old

Definitions

  1. ten-year; decennial; ten-year-old

Ancestry of “десятилетний”, step by step

десятилетний traces back through two separate lines of ancestry.

via Russian де́сять

StepLanguageWordMeaning
1Russianде́сятьten
2Old Church Slavonicдесѧтьten
3Proto-Slavicdesętьten
4Proto-Balto-Slavic*déśimtten
5Proto-Indo-Europeandéḱm̥tten

via Russian ле́то

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