Where does “sers-eh₂” come from?

sers-eh₂ (Proto-Indo-European) comes from Proto-Indo-European sers-, from Proto-Indo-European ser- — to flow; to guard; to bind, to tie together.

Ancestry of “sers-eh₂”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	sers-	to cut off
2	Proto-Indo-European	ser-	to flow; to guard; to bind, to tie together

sers-eh₂ — Etymology, Origin & Word History | Etymology Explorer