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

The working theory is that there's a deep magma chamber underneath the sea floor, sending molten rock upward and then contracting. David Grossman, Popular Mechanics, "Where Did This Massive Underwater Volcano Come From?," 22 May 2019 Even its core is believed to contain icy materials, while most other planets have rocky, molten cores. Jill Kiedaisch, Popular Mechanics, "Hubble Observes Ice Giant Vortexes and Polar Storms on Neptune and Uranus," 9 Feb. 2019 Solar thermal systems direct concentrated sunlight to a central tower to heat molten salt, which can store that heat for a long time before it's used. Megan Geuss, Ars Technica, "Using molten salt to store electricity isn’t just for solar thermal plants," 24 Dec. 2018 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 In nature, a whole range of geologic reactions can result when molten rock and water meet. Jill Kiedaisch, Popular Mechanics, "Scientists Blew Up Lava in a Backyard Volcano to Unlock the Secrets of the Most Violent Eruptions," 11 Dec. 2018 From the widening gash, molten rock burbled and splashed, then shot dozens of feet in the air. Author: Amy B Wang, Anchorage Daily News, "‘Pele’s the boss’: Hawaiians ride out uncertainty as lava devours more Big Island homes," 8 May 2018 From the widening gash, molten rock burbled and splashed, then shot dozens of feet in the air. Amy B Wang,, "'This is heartbreaking': Lava burns more homes on Hawaii's Big Island as new fissures form," 7 May 2018 From the gash, molten rock burbled and splashed, then shot as high as 80 to 100 feet in the air. The Washington Post,, "'Fast-moving situation': Lava shoots through Hawaii neighborhood," 6 May 2018

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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Statistics for molten

Last Updated

31 May 2019

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

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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

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