Where does “finster” come from?

finster (Old Swedish) comes from Middle Low German vinster, from Latin fenestra, from Etruscan *𐌚𐌍𐌄𐌔𐌕𐌓𐌀.

Ancestry of “finster”, step by step

Step	Language	Word	Meaning
1	Middle Low German	vinster	—
2	Latin	fenestra	a window, an opening for light; a breach; a...
3	Etruscan	*𐌚𐌍𐌄𐌔𐌕𐌓𐌀	—

finster — Etymology, Origin & Word History | Etymology Explorer