Where does “bʰórs-o-s” come from?

bʰórs-o-s (Proto-Indo-European) comes from Proto-Indo-European bʰers- — top, tip, point.

Ancestry of “bʰórs-o-s”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	bʰers-	top, tip, point