permafrost

noun

per·​ma·​frost ˈpər-mə-ˌfrȯst How to pronounce permafrost (audio)
: a permanently frozen layer at variable depth below the surface in frigid regions of a planet (such as earth)

Examples of permafrost in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Markus Stoffel, professor for climate change and natural risks at the University of Geneva, said climate change leads to the melting of both glaciers and permafrost. — ABC News, 18 Aug. 2026 Scientists have learned that as soon as summer temperatures thaw layers of the permafrost, its carbon turns into a bedazzling buffet for microbes. — Denise Hruby, Miami Herald, 31 July 2026 Researchers involved in the study expect these dynamics to intensify as flash droughts become more common, groundwater levels continue to decline, and permafrost retreats across the north. — Phil De Luna, Forbes.com, 27 July 2026 As Earth warms, an important source of methane is thawing permafrost, the permanently frozen ground found mostly in the Arctic. — Vahe Peroomian, The Conversation, 13 July 2026 See All Example Sentences for permafrost

Word History

Etymology

permanent + frost

First Known Use

1943, in the meaning defined above

Time Traveler
The first known use of permafrost was in 1943

Rhymes for permafrost

See All Rhymes for permafrost

Browse Nearby Words

permaculture
permafrost
permalloy
See all Nearby Words

Cite this Entry

“Permafrost.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/permafrost. Accessed 21 Aug. 2026.

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Kids Definition

permafrost

noun
per·​ma·​frost ˈpər-mə-ˌfrȯst How to pronounce permafrost (audio)
: a permanently frozen layer at variable depth below the surface in frigid regions of a planet (as earth)

More from Merriam-Webster on permafrost

Britannica.com: Encyclopedia article about permafrost

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