hydrothermal

American  

[hahy-druh-thur-muhl] / ˌhaɪ drəˈθɜr məl /

adjective

Geology.

1. noting or pertaining to the action of hot, aqueous solutions or gases within or on the surface of the earth.

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hydrothermal British  

/ ˌhaɪdrəʊˈθɜːməl /

adjective

1. of or relating to the action of water under conditions of high temperature, esp in forming rocks and minerals

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hydrothermal Scientific  

/ hī′drə-thûr′məl /

1. Relating to or produced by hot water, especially water heated underground by the Earth's internal heat.

2. ◆ Hydrothermal energy is power that is generated using the Earth's hot water.

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Other Word Forms

• hydrothermally
  adverb

Etymology

Origin of hydrothermal

First recorded in 1840–50; hydro- ¹ + thermal

Explanation

The adjective hydrothermal is used to describe hot water, particularly water that's heated underground. If you visit Yellowstone, you'll probably see hydrothermal attractions like geysers and hot springs. Hydrothermal derives from Greek roots hydor, "water," and therme, "heat." It's been used by geologists since the 1850s to describe underground hot water. Hydrothermal activity occurs all over the planet, and it's especially common around active volcanoes. As well as steamy hot springs and dramatic geysers shooting hot water into the air, smaller mud pots and hydrothermal vents in the ocean floor are also evidence of water heating up beneath the earth's surface.

Example Sentences

See Examples For:

hydrothermal

Some of the animals seen by the scientists also live in hydrothermal vents and cold seeps, suggesting whale carcasses could help connect these deep-sea communities.

From Barron's ● Jun. 10, 2026

US palaeontologist Stephen Godfrey compared the "truly unique discovery" to past major underwater finds, such as when scientists first identified hydrothermal vents teeming with life on the ocean floor in 1977.

From Barron's ● Jun. 10, 2026

Taken together, the findings support the idea that the stromatolites developed inside a hydrothermal lake created after the asteroid impact and continued forming as the environment gradually cooled.

From Science Daily ● May 22, 2026

The study focuses on hydrothermal vents, where heated, mineral-laden water moves through rock and into surrounding water, creating the right energy and chemistry for complex reactions.

From Science Daily ● Apr. 3, 2026

Such corrections are impossible unless a proper determination of the hydrothermal equivalent has been made.

From Respiration Calorimeters for Studying the Respiratory Exchange and Energy Transformations of Man by Benedict, Francis Gano