mol·​ten | \ ˈmōl-tᵊn How to pronounce molten (audio) \

Definition of molten

1 : fused or liquefied by heat : melted molten lava
2 : having warmth or brilliance : glowing the molten sunlight of warm skies— T. B. Costain
3 obsolete : made by melting and casting

Examples of molten in a Sentence

Recent Examples on the Web Both have iron-rich cores, mantles filled with churning molten rock, and thin, rocky crusts that cover their surface. Jennifer Leman, Popular Mechanics, "This Is Venus, Earth's Boiling Twin," 5 Jan. 2020 Quartz sand is refined into molten silicon with a purity of 99.999999999%. The Economist, "A look inside the factory around which the modern world turns," 18 Dec. 2019 In some instances, tracking the activity of magmatic eruptions—where molten rock rises from deep within Earth’s mantle—can be more straightforward. Jennifer Leman, Popular Mechanics, "Why the White Island Volcano Eruption Was So Dangerous," 11 Dec. 2019 That target contains some material, typically either molten salt or a fluid that transfers heat readily, in order to heat it. John Timmer, Ars Technica, "Company claims breakthrough in concentrating the Sun’s rays," 19 Nov. 2019 Another, Terrestrial Energy, in Canada, is developing a design that uses molten salt to produce 195 megawatts per reactor, about one-fifth of conventional units. Andrew Blum, Time, "The Tech Innovations We Need to Happen if We're Going to Survive Climate Change," 12 Sep. 2019 The central tower houses molten salts that can store the energy of that light for extended periods of time. Shweta Narayan, Smithsonian, "How Engineers of New Energy Technology Are Taking Cues From Nature," 31 Aug. 2019 In its place, the NASA team came up with a class of organic compounds called ionic liquids, essentially molten salts, that would remain liquid in the frigid lunar night. Daniel Clery, Science | AAAS, "Could humanity’s return to the moon spark a new age of lunar telescopes?," 18 July 2019 Some startups are developing low-temperature, low-pressure reactors that use molten salt rather than water to cool fuel rods. Eric Niiler, WIRED, "Senators Try—Again—to Solve the Nuclear Waste Debacle," 28 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'molten.' 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 molten

14th century, in the meaning defined at sense 3

History and Etymology for molten

Middle English, from past participle of melten to melt

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Time Traveler for molten

Time Traveler

The first known use of molten was in the 14th century

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Statistics for molten

Last Updated

25 Jan 2020

Cite this Entry

“Molten.” The Dictionary, Merriam-Webster Inc., Accessed 28 January 2020.

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More Definitions for molten


How to pronounce molten (audio)

English Language Learners Definition of molten

: melted by heat


mol·​ten | \ ˈmōl-tᵊn How to pronounce molten (audio) \

Kids Definition of molten

: melted especially by very great heat molten metal

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More from Merriam-Webster on molten

Thesaurus: All synonyms and antonyms for molten

Spanish Central: Translation of molten

Nglish: Translation of molten for Spanish Speakers

Comments on molten

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


showing steady, earnest care and effort

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