mag·​ma | \ ˈmag-mə \

Definition of magma

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

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Other Words from magma

magmatic \ mag-​ˈma-​tik \ adjective

Examples of magma in a Sentence

Recent Examples on the Web

Beneath Indonesia, plates are colliding, forcing one beneath the other and in the process melting the plates and sending molten magma toward the surface. Jake Maxwell Watts, WSJ, "Indonesia’s Volatile Child of Krakatau Collapsed, but Now It’s More Explosive," 29 Dec. 2018 Since late April, that lake has been receding into its magma column, the vertical passage that brings magma from Earth's interior up to the crater. Sarah Gibbens, National Geographic, "Will the Eruptions From Hawaii's Kilauea Volcano Turn Explosive? Get the Facts.," 10 May 2018 Mid-ocean ridges—gaps in the Earth's crust on the seafloor—leak magma into the ocean, which then hardens and is pushed out of the way by more magma. Sophie Weiner, Popular Mechanics, "Dinosaur-Killing Asteroid May Have Also Triggered Undersea Volcano Eruptions," 9 Feb. 2018 Don Swanson, a geologist with the Hawaiian Volcano Observatory, said the magma is likely to drop below the water table around the middle of the month. Fox News, "Scientists: Kilauea volcano may have explosive eruption," 11 May 2018 Neal said fresher, hotter lava could emerge because magma has been moving down Kilauea's rift zone toward the area where the volcano is erupting. CBS News, "Hawaii Kilauea volcano eruption: More Big Island residents told to be prepared to evacuate," 11 May 2018 The United Nations world heritage site, which lies over giant chambers of molten magma, is actually the world’s largest supervolcano, which erupted 2.1 million, 1.3 million and 640,000 years ago, causing massive devastation across the planet. Fox News, "Quakes and eruptions spark talks of Yellowstone supervolcano," 2 Oct. 2018 Lave tubes are long, narrow structures by flowing lava in volcanoes, while lava dikes are vertical sheets of magma injected into the lunar crust. David Grossman, Popular Mechanics, "The Moon's Most Mysterious Feature Now Has an Origin Story," 7 Sep. 2018 Days later, after several small earthquakes, the magma pushed its way back to the surface on the east side of the island's Leilani Estates neighborhood, creating the first of many fissures to come. Amy B Wang, ajc, "Lava spatter hits Hawaii man and shatters his leg in first known injury from Kilauea volcano," 20 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'magma.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of magma

15th century, in the meaning defined at sense 1

History and Etymology for magma

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

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Statistics for magma

Last Updated

23 Jan 2019

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Time Traveler for magma

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

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More Definitions for magma



English Language Learners Definition of magma

technical : hot liquid rock below the surface of the Earth


mag·​ma | \ ˈmag-mə \

Kids Definition of magma

: molten rock within the earth


mag·​ma | \ ˈmag-mə \

Medical Definition of magma

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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More from Merriam-Webster on magma

Spanish Central: Translation of magma

Nglish: Translation of magma for Spanish Speakers Encyclopedia article about magma

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