permafrost

noun

per·​ma·​frost ˈpər-mə-ˌfrȯst 

: 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

Shugar notes that changes in the weather could have contributed to the conditions that caused this flood, not just the melting of permafrost. — Thor Benson, Rolling Stone, 2 Sep. 2026

An incident of the massive scale seen in Nepal is rare, but smaller, similar disasters will be more frequent in the future as the melting of glaciers and permafrost creates unstable bedrock in mountains, according to Cook. — Megan Fahrney, ABC News, 1 Sep. 2026

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

Word History

Etymology

permanent + frost

First Known Use

1943, in the meaning defined above

Rhymes for permafrost

• holocaust
• accost
• crisscrossed
• defrost
• embossed
• exhaust
• recrossed
• uncrossed
• bossed
• cost
• crossed
• dost

Kids Definition

permafrost

noun

per·​ma·​frost ˈpər-mə-ˌfrȯst 

: a permanently frozen layer at variable depth below the surface in frigid regions of a planet (as earth)