Origin and history of gush

1780, extended from Icelandic Geysir, name of a specific hot spring in the valley of Haukadal, literally "the gusher," from Old Norse geysa "to gush," from Proto-Germanic *gausjan, suffixed form of PIE *gheus-, extended form of the root *gheu- "to pour." Taken by foreign writers as the generic name for spouting hot springs, for which the native Icelandic words are hverr "a cauldron," laug "a hot bath."

"oil well that flows without pumping," 1886, agent noun from gush (v.). Earlier in a sense of "overly effusive person" (1864).