Definition of permafrost
: a permanently frozen layer at variable depth below the surface in frigid regions of a planet (such as earth)
From the M-W Editors
Recent Examples of permafrost from the Web
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Only surface layers of soil thaw under the 24/7 stare of the midsummer sun. Because the deep permafrost never melts, water pools on the tundra with nowhere to drain, creating perfect breeding grounds for the beasts.
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For example, scientists recognize that the melting permafrost will probably release carbon into the atmosphere.
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Mann only disputed the threat posed by the release of methane frozen in permafrost, and the characterization of a study about the pace of global warming.
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Woolly mammoth are surfacing all the time as the permafrost slowly melts.
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Its plain, boxy buildings sit on stilts to prevent their thawing the permafrost below.
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There are, as of this writing, no woolly mammoths yet trampling the permafrost.
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Its plain, boxy buildings sit on stilts to prevent thawing the permafrost below.
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Along the way were clouds of mosquitoes, boggy land, permafrost and temperatures ranging from 90 degrees to minus 70 during one of the coldest years on record.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'permafrost.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of permafrost
permanent + frost
PERMAFROST Defined for English Language Learners
permafrost
playDefinition of permafrost for English Language Learners
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: a layer of soil that is always frozen in very cold regions of the world
Learn More about permafrost
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See words that rhyme with permafrost Britannica.com: Encyclopedia article about permafrost
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