Where does “*tíśtis” come from?

*tíśtis (Proto-Balto-Slavic) comes from Proto-Indo-European teḱ- — to sire, beget.

Ancestry of “*tíśtis”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	teḱ-	to sire, beget

*tíśtis — Etymology, Origin & Word History | Etymology Explorer