permafrost

[ pur-muh-frawst, -frost ]
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noun
  1. (in Arctic or subarctic regions) perennially frozen subsoil.

Origin of permafrost

1
First recorded in 1943; perma(nent) + frost

Words Nearby permafrost

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British Dictionary definitions for permafrost

permafrost

/ (ˈpɜːməˌfrɒst) /


noun
  1. ground that is permanently frozen, often to great depths, the surface sometimes thawing in the summer

Origin of permafrost

1
C20: from perma (nent) + frost

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

Scientific definitions for permafrost

permafrost

[ pûrmə-frôst′ ]


  1. A layer of soil or bedrock that has been continuously frozen for at least two years and as long as tens of thousands of years. Permafrost can reach depths of up to 1,524 m (4,999 ft). It is found throughout most of the polar regions and underlies about one fifth of the Earth's land surface.

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