Where does “zacym” come from?

zacym (Polish) comes from Polish co, from Old Polish czso, from Proto-Slavic česo, from Proto-Slavic čь, from Proto-Balto-Slavic ki, from Proto-Indo-European kʷíd, from Proto-Indo-European kʷís, from Proto-Indo-European kʷi- — interrogative base.

Ancestry of “zacym”, step by step

StepLanguageWordMeaning
1Polishcowhat; Used together with a noun to indicate how...
2Old Polishczsowhat
3Proto-Slavicčesowhat (interrogative)
4Proto-Slavicčьwhat; alternative form of *čьto
5Proto-Balto-Slavickiwhat
6Proto-Indo-Europeankʷídneuter nominative/accusative singular of *kʷís
7Proto-Indo-Europeankʷíswho, what; who, which, that; which, what
8Proto-Indo-Europeankʷi-interrogative base
Every word from Proto-Indo-European kʷi-Every word from Proto-Indo-European kʷísEvery word from Proto-Indo-European kʷíd