Where does “ûziębnąć” come from?

ûziębnąć (Polish) comes from Polish ziębnąć, from Proto-Slavic zębnǫti, from Proto-Slavic zęti, from Proto-Balto-Slavic źemb-, from Proto-Indo-European ǵembʰ- — to bite, chew; tooth, nail; to pierce, gnaw...

Ancestry of “ûziębnąć”, step by step

Step	Language	Word	Meaning
1	Polish	ziębnąć	to freeze; to cool
2	Proto-Slavic	zębnǫti	to suffer from cold; to germinate
3	Proto-Slavic	zęti	to freeze?
4	Proto-Balto-Slavic	źemb-	—
5	Proto-Indo-European	ǵembʰ-	to bite, chew; tooth, nail; to pierce, gnaw...

Every word from Proto-Indo-European ǵembʰ- →Every word from Proto-Balto-Slavic źemb- →Every word from Proto-Slavic zęti →