The English word ‘geyser’ (“a periodically sprouting hot spring”) derives from Geysir. That name itself is derived from the Icelandic verb ‘geysa’ (“to gush”) from the Old Norse.
This is actually a nearby geyser named Strokkur (“the churn”) which erupts more frequently than Geysir (which was right behind me), and to heights of up to 30 meters every few minutes.