Where does “*ʒ₁wel-” come from?

*ʒ₁wel- (Proto-Georgian-Zan) comes from Proto-Kartvelian ʒ₁w- — to be old.

Ancestry of “*ʒ₁wel-”, step by step

Step	Language	Word	Meaning
1	Proto-Kartvelian	ʒ₁w-	to be old