Where does “беревно́” come from?

беревно́ (Russian) comes from Old Church Slavonic бьрьвьно, from Proto-Slavic bьrvьno.

Ancestry of “беревно́”, step by step

StepLanguageWordMeaning
1Old Church Slavonicбьрьвьно—
2Proto-Slavicbьrvьno—
Every word from Proto-Slavic bьrvьno →Every word from Old Church Slavonic бьрьвьно →