jökulhlaup

jö·kul·hlaup

(yŭ′kəl-hloup′, -hlōp′, -hlo͞op′, yō′-; yœ′kül-hlœp′)
n. pl. jö·kul·hlaups
The sudden, catastrophic release of meltwater from beneath or behind a glacier.

[Icelandic : jökull, glacier (from Old Norse jǫkull, icicle, ice; akin to Old English gicel, icicle) + hlaup, run, sudden rise of a river, flood (from Old Norse, leap, from hlaupa, to leap; akin to Old English hlēapan).]