Where does “twor(ʔ)-o” come from?

twor(ʔ)-o (Proto-Balto-Slavic) comes from Proto-Indo-European tworH-o-.

Ancestry of “twor(ʔ)-o”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	tworH-o-	—

twor(ʔ)-o — Etymology, Origin & Word History | Etymology Explorer