Where does “Basia” come from?

Basia (Polish) comes from Polish Barbara, from Ancient Greek βάρβαρος, from Proto-Indo-European balb-.

Ancestry of “Basia”, step by step

StepLanguageWordMeaning
1PolishBarbara—
2Ancient Greekβάρβαροςnon-Greek-speaking, foreign; barbaric, brutal,...
3Proto-Indo-Europeanbalb-—
Every word from Proto-Indo-European balb- →Every word from Ancient Greek βάρβαρος →Every word from Polish Barbara →