An Etymological Dictionary of the German Language/Annotated/Strom
Strom, masculine, ‘stream, torrent, current,’ from the equivalent Middle High German strôm (stroum), Old High German stroum; common to Teutonic in the form straumo-. Compare Old Saxon strôm, Dutch stroom, Anglo-Saxon streám, English stream, and the equivalent Old Icelandic straumr. Teutonic straumo- for srou-mo- is based on the Aryan root srū̆ (srou), ‘to flow,’ which appears in Greek ῥέω (for *σρέϝω; ῥύσις, ‘flowing,’ for sru-ti-s), Sanscrit root sru, ‘to flow,’ Old Irish sruth, ‘river,’ and sruaim (base sroumen), ‘stream.’ For the evolution of Aryan sr to str see Schwester and Strick.