# permafrost

/pˈɜːmɐfɹˌɒst/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/permafrost
Updated: 2026-05-26

## Definition

soil, rock, or sand that stays frozen for at least two years. It is found in very cold places like the Arctic and Antarctica.

For teachers: ground that remains frozen for two or more consecutive years. It consists of soil, rock, or sediment that remains below 0°C for extended periods.

## Examples

- The melting of permafrost can cause the ground to sink.
- Scientists are studying how the thawing of permafrost in Siberia releases large amounts of methane into the atmosphere.
- The structural integrity of many northern communities is directly tied to the stability of the permafrost, which is increasingly vulnerable to the rapid warming of the polar regions.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.