Where does “trzyniok” come from?

trzyniok (Polish) comes from Polish trzy, from Proto-Slavic trьje, from Proto-Balto-Slavic tríjes, from Proto-Indo-European *tréyes.

Ancestry of “trzyniok”, step by step

StepLanguageWordMeaning
1Polishtrzythree
2Proto-Slavictrьjethree
3Proto-Balto-Slavictríjesthree
4Proto-Indo-European*tréyes—
Every word from Proto-Indo-European *tréyes →Every word from Proto-Balto-Slavic tríjes →Every word from Proto-Slavic trьje →