Where does “основно” come from?

основно (Bulgarian) comes from Bulgarian осно́вен, from Russian осно́ва, from Old East Slavic основа, from Proto-Slavic osnova — basis, foundation.

основно (Bulgarian): basically, fundamentally

Definitions

  1. basically, fundamentally

Ancestry of “основно”, step by step

StepLanguageWordMeaning
1Bulgarianосно́венbasic, fundamental, principal, main
2Russianосно́ваbasis, foundation
3Old East Slavicоснова—
4Proto-Slavicosnovabasis, foundation
Every word from Proto-Slavic osnova →Every word from Old East Slavic основа →Every word from Russian осно́ва →