Other forms: gushing, gushed, gushes
To gush is to pour out in a strong stream. Water from a burst pipe, blood from a cut, oil from a new well.
The flow is sudden and heavy, which is what separates it from trickle or seep. The figurative sense is about talk rather than liquid, and to gush over somebody is to praise them so warmly that it becomes embarrassing. That use is nearly always a criticism, and gushing praise is praise nobody quite trusts. As a noun a gush is the surge itself, and a gusher is an oil well that comes in under its own pressure.
Proto-Indo-European
*ǵʰew-
Old Norse
gusa — to gush
Middle Dutch
guysen — to flow out with a gurgling sound, gush
Middle English
guschen
English, today
gush
From Middle English guschen, gusshen, gosshien, perhaps from Middle Dutch guysen (“to flow out with a gurgling sound, gush”) or Old Norse gusa (“to gush”), ultimately imitative of the sound. Compare Old Norse geysa (“to gush”), German gießen (“to pour”), Old English ġēotan "to pour"; > English yote. Related to gust.
Etymology from Wiktionary, CC BY-SA