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.
In the past, information about where permafrost was changing was primarily available through scientific studies published years later. — Anna Liljedahl, Fortune, 29 Aug. 2026 High mountain slopes are also held together by permafrost – ground that stays frozen year-round – with ice filling the cracks and joints in the rock like a natural cement. — Umesh Haritashya, The Conversation, 29 Aug. 2026 Sabrina Blanchard and Luca Matteucci/AFP/Getty The Hindu Kush Himalayan region is warming rapidly, driving major changes in glaciers, snow cover, permafrost and mountain slopes, according to climate scientists. — CBS News, 28 Aug. 2026 As temperatures rise, ice melts, permafrost thaws and the landscape shifts. — Laura Paddison, CNN Money, 28 Aug. 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 1 Sep. 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

Last Updated: - Updated example sentences
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