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

The team found that phosphite, a form of phosphorus naturally found in hydrothermal vents, can react with organic compounds in the presence of palladium and produce reactions associated with metabolic phosphorylation.

From Science Daily ● Aug. 12, 2026

The same mechanism could help explain why hydrothermal sulfide deposits along submarine island arcs often contain unusually large amounts of gold.

From Science Daily ● Jul. 29, 2026

According to the simulations, a single large impact during this early period could have generated as much as 100 times the hydrothermal activity found across the Yellowstone region today.

From Science Daily ● Jul. 2, 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

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 Francis Gano Benedict