magma

noun

mag·​ma ˈmag-mə How to pronounce magma (audio)
1
archaic : dregs, sediment
2
: a thin pasty suspension (as of a precipitate in water)
3
: molten rock material within the earth from which igneous rock results by cooling
magmatic adjective

Examples of magma in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
An increase in gas emissions confirms that new magma has entered the Earth’s crust beneath the volcano, indicating that an eruption is likely in the next weeks or months, according to the observatory. Julia Jacobo, ABC News, 13 Mar. 2025 Fresh magma has intruded into the Earth’s crust underneath Alaska’s Mount Spurr, 75 miles west of Anchorage, increasing the likelihood of an eruption within the near future, government officials said Wednesday afternoon. Marc Ramirez, USA TODAY, 12 Mar. 2025 Off the coast of Japan, thousands of feet below the surface, the seafloor explodes with heat. Cracks and vents in the rocky sediment allow boiling seawater heated by subterranean magma to shoot back up into the sea, reaching temperatures of more than 700 degrees Fahrenheit. Irene Wright, Miami Herald, 10 Feb. 2025 Puy de Dôme formed about 11,000 years ago when a fist of magma punched up into the rolling hills of central France. Carl Zimmer, Smithsonian Magazine, 25 Feb. 2025 See All Example Sentences for magma

Word History

Etymology

Middle English, from Latin magmat-, magma, from Greek, thick unguent, from massein to knead — more at mingle

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of magma was in the 15th century

Browse Nearby Words

Cite this Entry

“Magma.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/magma. Accessed 19 Mar. 2025.

Kids Definition

magma

noun
mag·​ma ˈmag-mə How to pronounce magma (audio)
: molten rock material within the earth
magmatic adjective

Medical Definition

magma

noun
mag·​ma ˈmag-mə How to pronounce magma (audio)
1
: a crude mixture of mineral or organic matter in the state of a thin paste
2
: a suspension of a large amount of precipitated material (as in milk of magnesia) in a small volume of a watery vehicle

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