Where does “helviti” come from?

helviti (Old Norse) comes from Old Norse viti, from Proto-Germanic wītiją, from Proto-Indo-European weyd- — to see.

Ancestry of “helviti”, step by step

Step	Language	Word	Meaning
1	Old Norse	viti	indicator; token, mark, signal; beacon
2	Proto-Germanic	wītiją	punishment
3	Proto-Indo-European	weyd-	to see

helviti — Etymology, Origin & Word History | Etymology Explorer