Where does “wr̥su-” come from?

wr̥su- (Proto-Indo-European) comes from Proto-Indo-European wer- — to burn; to cover, heed, notice; squirrel.

Ancestry of “wr̥su-”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	wer-	to burn; to cover, heed, notice; squirrel

wr̥su- — Etymology, Origin & Word History | Etymology Explorer