Where does “fiädhal” come from?

fiädhal (Old Swedish) comes from Old Norse fiðrildi, from Proto-Germanic fifaldǭ, from Proto-Indo-European pāpel-.

Ancestry of “fiädhal”, step by step

Step	Language	Word	Meaning
1	Old Norse	fiðrildi	—
2	Proto-Germanic	fifaldǭ	butterfly
3	Proto-Indo-European	pāpel-	—

fiädhal — Etymology, Origin & Word History | Etymology Explorer