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nuée ardente

American  
[ny-ey ar-dahnt] / nü eɪ arˈdɑ̃t /

noun

Geology.

plural

nuées ardentes
  1. (in a volcanic eruption) a swiftly flowing, dense cloud of hot gases, ashes, and lava fragments.


nuée ardente British  
/ ˈnyeɪ ɑːˈdɑ̃t /

noun

  1. a rapidly moving turbulent incandescent cloud of gas, ash, and rock fragments flowing close to the ground after violent ejection from a volcano See also ignimbrite

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

nuée ardente Scientific  
/ no̅o̅-āăr-dänt /

plural

nuées ardentes
  1. A fast moving gaseous cloud of hot ashes and other material thrown out from an erupting volcano. Nuées ardentes are often incandescent.


Etymology

Origin of nuée ardente

1900–05; < French: literally, burning cloud