jökulhlaup
YUR-kul-loip
A sudden, catastrophic flood caused by the release of water from beneath or within a glacier — often triggered by volcanic activity beneath an ice cap, or by the failure of an ice dam holding back a glacial lake. Jökulhlaups can discharge millions of cubic feet of water per second, reshaping valleys in hours. Iceland, with its volcanoes under ice caps, is the type locality.
Etymology
Icelandic — jökull (glacier) + hlaup (run, rush). A glacier run. The word is used internationally because no other language has a single term for the phenomenon.
Notes
One of the great words in the project. Untranslatable, onomatopoeic in Icelandic, and describing something so specific and so catastrophic that English had to borrow it wholesale.
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