Where does “*kistis” come from?

*kistis (Proto-Balto-Slavic) comes from Proto-Indo-European (s)kʷit-tis.

Ancestry of “*kistis”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	(s)kʷit-tis	—

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