# hydrothermal

/ˌhaɪdɹoʊˈθɝməɫ/ (US) · /hˌaɪdɹəðˈɜːməl/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/hydrothermal
Updated: 2026-06-22

## Definition

relating to water that is very hot and under high pressure. This usually happens deep under the Earth's surface or near volcanoes.

For teachers: relating to or caused by the action of hot water under high pressure, typically in the Earth's crust. Often describes the formation of mineral deposits or the activity of deep-sea vents.

## Examples

- The miners found gold in a hydrothermal vein.
- Scientists study hydrothermal vents on the ocean floor because they support unique life forms that do not rely on sunlight.
- The formation of the ore body was facilitated by hydrothermal fluids that leached metals from the surrounding rock and deposited them as the water cooled and lost pressure.

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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.