Where does “Jezierny” come from?

Jezierny (Polish) comes from Polish jezioro, from Old Polish jeziero, from Proto-Slavic ȅzero, from Proto-Balto-Slavic *éźeran — lake.

Ancestry of “Jezierny”, step by step

StepLanguageWordMeaning
1Polishjeziorolake
2Old Polishjeziero—
3Proto-Slavicȅzerolake
4Proto-Balto-Slavic*éźeranlake
Every word from Proto-Balto-Slavic *éźeran →Every word from Proto-Slavic ȅzero →Every word from Old Polish jeziero →