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

"This is the first comprehensive evidence suggesting that stromatolites could form in hydrothermal lakes created by asteroid impacts," said Dr. Jaesoo Lim, lead author of the study.

From Science Daily • May 22, 2026

The inner portions of the stromatolites showed stronger hydrothermal signatures, indicating they likely formed during an earlier and hotter stage of the crater lake's history.

From Science Daily • May 22, 2026

Traditionally, scientists have focused on environments such as drying pools on land or hydrothermal vents in the deep ocean as likely settings for the origin of life.

From Science Daily • Apr. 29, 2026

Her analysis highlights hydrothermal systems formed by meteor impacts as an overlooked but potentially important setting for life's beginnings.

From Science Daily • Apr. 3, 2026

These occurrences are generally held to be due to hydrothermal or geyser action.

From Getting Gold: a practical treatise for prospectors, miners and students by Johnson, J. C. F. (Joseph Colin Frances)