mag·​ma | \ ˈmag-mə How to pronounce magma (audio) \

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 How to pronounce magmatic (audio) \ adjective

Examples of magma in a Sentence

Recent Examples on the Web

One of the most influential hypotheses to come from the lunar samples is the idea that there was an ocean of magma on the early moon. Erica Jawin, Scientific American, "Apollo’s Bounty: The Science of the Moon Rocks," 2 July 2019 Debate ensued among seismologists over the chances of a major eruption; some saw evidence that molten magma below the Earth’s crust was rising. Matthew Berger, Discover Magazine, "Forecasting Doom: New Tech Could Help Predict Volcanic Eruptions," 30 June 2019 Scientists concluded that a small amount of magma was injected about 2.5 miles (4 kilometers) under the northern portion of the caldera. Emilie Hooft, The Conversation, "We probed Santorini’s volcano with sound to learn what’s going on beneath the surface," 24 June 2019 Volcanic ash forms thanks to the expansion of gases within the rising magma. Maya Wei-haas, Smithsonian, "A Brief Glossary of Volcano Vocab," 25 May 2018 According to the paper, during the impact the Earth was covered in a giant ocean of magma. Avery Thompson, Popular Mechanics, "The Moon May Have Formed From a Molten Magma Ocean on Earth," 1 May 2019 There’s more magma (underground lava) in the system to be erupted. Doyle Rice, USA TODAY, "Hawaii volcano: The science behind the eruption of Kilauea," 7 May 2018 Earth's only natural satellite still had a molten core, and gases escaping from underground magma would have produced an atmosphere. Avery Thompson, Popular Mechanics, "Life May Have Once Existed on the Moon," 24 July 2018 Scientists say the older lava is likely from magma that Kilauea has been storing underground since the volcano last erupted in 1955. Washington Post, "Faster-moving Hawaii lava gushes into sea, spews new danger," 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

10 Jul 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 How to pronounce magma (audio) \

Kids Definition of magma

: molten rock within the earth


mag·​ma | \ ˈmag-mə How to pronounce magma (audio) \

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

Comments on magma

What made you want to look up magma? Please tell us where you read or heard it (including the quote, if possible).


appealing forcibly to the mind or reason

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