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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.
Meanwhile, volcano experts have collected samples to determine the magma type and verify whether the volcano was truly dormant for 12,000 years. Mrigakshi Dixit, Interesting Engineering, 25 Nov. 2025 Marzocchi says the data suggest that, for now, the tremors are more the result of gases pushing superheated water up through the earth, rather than magma rising. Ruth Sherlock, NPR, 25 Nov. 2025 The data revealed that when lake levels were lower during drier periods, fault lines moved faster and magma flux was higher. New Atlas, 25 Nov. 2025 These will help reveal what kind of magma caused the eruption, Biggs says. Stephanie Pappas, Scientific American, 24 Nov. 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 1 Dec. 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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