Where does “tuh₂-ró-s” come from?

tuh₂-ró-s (Proto-Indo-European) comes from Proto-Indo-European tewh₂- — to swell; to crowd; to be strong.

Ancestry of “tuh₂-ró-s”, step by step

Step	Language	Word	Meaning
1	Proto-Indo-European	tewh₂-	to swell; to crowd; to be strong

tuh₂-ró-s — Etymology, Origin & Word History | Etymology Explorer