Where does “rheo-” come from?

rheo- (English) comes from Ancient Greek ῥέω, from Proto-Indo-European srew-, from Proto-Indo-European ser- — to flow; to guard; to bind, to tie together.

rheo- (English): flow, current

Definitions

flow, current

Ancestry of “rheo-”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	ῥέω	I flow, stream, run, gush; I let flow, pour; I...
2	Proto-Indo-European	srew-	to flow, stream
3	Proto-Indo-European	ser-	to flow; to guard; to bind, to tie together

Words derived from “rheo-”

rheostat
rheometer
rheostatic
rheologic
rheometry
rheophore
rheotome
rheobase
rheotaxis
rheophilic
rheometric
rheopectic
rheotrope
rheotropism
rheocasting
hemorheologic
rheopexy
rheotactic
rheophile
rheophyte
rheoscope
rheogoniometer
rheographic
rheoplethysmograph

Every word from Proto-Indo-European ser- →

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