Where does “hion” come from?

hion (Old Swedish) comes from Old Norse [[hjón]], [[hjún]], [[hjú]], from Proto-Germanic *hīwōnō.

Ancestry of “hion”, step by step

Step	Language	Word	Meaning
1	Old Norse	[[hjón]], [[hjún]], [[hjú]]	—
2	Proto-Germanic	*hīwōnō	—

hion — Etymology, Origin & Word History | Etymology Explorer