Rhine

Proto-Indo-European root meaning "to flow, run."

It forms all or part of: derive; ember-days; rennet (n.1); Rhine; rialto; rill; rio; rival; rivulet; run; runnel.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit rinati "causes to flow," ritih "stream, course;" Latin rivus "stream;" Old Church Slavonic reka "river;" Middle Irish rian "river, way;" Gothic rinnan "run, flow," rinno "brook;" Middle Low German ride "brook;" Old English riþ "stream;" Old English rinnan, Old Norse rinna "to run," Dutch ril "running stream."

"of or belonging to the River Rhine or its region," late 14c., Rinish, from Rine, or from Anglo-French reneis (13c.) or Medieval Latin Rhenensis, from Rhenus (see Rhine). Also partly from continental German forms such as Middle Low German rinish (German rheinisch). Originally and especially of wine, later also of architecture, etc.