Where does “повність” come from?

повність (Ukrainian) comes from Ukrainian по́вний, from Russian -ота́, from Proto-Slavic -ota, from Proto-Balto-Slavic -atā́ˀ, from Proto-Indo-European -otéh₂.

Ancestry of “повність”, step by step

Step	Language	Word	Meaning
1	Ukrainian	по́вний	full
2	Russian	-ота́	—
3	Proto-Slavic	-ota	Deadjectival, forming abstract nouns denoting the...
4	Proto-Balto-Slavic	-atā́ˀ	—
5	Proto-Indo-European	-otéh₂	—

Every word from Proto-Indo-European -otéh₂ →Every word from Russian -ота́ →Every word from Proto-Slavic -ota →