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 Over 60 hours, Novarupta released so much magma that, eventually, the ash made its way all around the world. Katie Orlinsky, National Geographic, "Retracing the explosive history of a remote national park in Alaska," 27 May 2020 Stefano Branca of the National Institute of Geophysics and Vulcanology (INGV) said the eruption was paroxysmal, meaning the eruption occurs when high-pressure magma explodes from a shallow, underground reservoir. Fox News, "Volcano erupts on Italian island popular with tourists, killing hiker on mountainside," 4 July 2019 Furthermore, the synestia’s torrential magma rains and turbulent vapors would have driven even more mixing throughout a large fraction of the body. Simon J. Lock, Scientific American, "When Earth and the Moon Were One," 2 July 2019 But geologists debate whether these bumpy landforms are really frozen magma. Charlie Wood, Popular Science, "Mud volcanoes on Mars hint at ancient water reservoirs," 21 May 2020 During a period of less than two months, a bulge the size of a town had appeared on its north flank, a vast pimple of unusually positioned magma. Robin George Andrews, New York Times, "The Mount St. Helens Eruption Was the Volcanic Warning We Needed," 18 May 2020 Under the surface, the mantle blob melted, turning from solid rock to fluid magma. Quanta Magazine, "Sudden Ancient Global Warming Event Traced to Magma Flood," 19 Mar. 2020 About 50 volcanic earthquakes were detected over eight hours Tuesday, indicating rising magma, the institute said. Joeal Calupitan, Anchorage Daily News, "Philippine volcano spews lava a half-mile high and coats towns in heavy ash," 14 Jan. 2020 Rock began to cool and crystallize, but iron stayed melted in the magma ocean, said Nicolas Coltice at the École Normale Supérieure in Paris. Quanta Magazine, "Continents of the Underworld Come Into Focus," 7 Jan. 2020

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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Time Traveler for magma

Time Traveler

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

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Statistics for magma

Last Updated

25 Jun 2020

Cite this Entry

“Magma.” Dictionary, Merriam-Webster, Accessed 10 Jul. 2020.

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More Definitions for magma


How to pronounce magma (audio)

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

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