Where does “семидневный” come from?

семидневный (Russian) comes from Russian семь, from Proto-Slavic sedmь, from Proto-Indo-European septḿ̥ — seven.

семидневный (Russian): seven-day

Definitions

  1. seven-day

Ancestry of “семидневный”, step by step

семидневный traces back through two separate lines of ancestry.

via Russian семь

StepLanguageWordMeaning
1Russianсемьseven
2Proto-Slavicsedmьseven
3Proto-Indo-Europeanseptḿ̥seven

via Russian день

StepLanguageWordMeaning
1Russianденьday, daytime; afternoon, early evening;...
2Old East Slavicдьньday
3Proto-Slavicdь̑nьday
Every word from Proto-Indo-European septḿ̥ →Every word from Proto-Slavic sedmь →Every word from Russian семь →
семидневный — Etymology, Origin & Word History | Etymology Explorer