ba·​salt | \ bə-ˈsȯlt How to pronounce basalt (audio) , ˈbā-ˌsȯlt How to pronounce basalt (audio) \

Definition of basalt

: a dark gray to black dense to fine-grained igneous rock that consists of basic plagioclase, augite, and usually magnetite

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Other Words from basalt

basaltic \ bə-​ˈsȯl-​tik How to pronounce basaltic (audio) \ adjective

Examples of basalt in a Sentence

Recent Examples on the Web

Although views are sparse on the summit, huge basalt shelves and jumbled boulders provide ample seating for a snack break or breather before taking on the final easy mile back to the trailhead. Mare Czinar, azcentral, "Arizona hike: Shady, easy-to-navigate forest trail leads to big mountain views," 21 June 2019 More than twenty years ago, sea lions discovered Willamette Falls, an enormous basalt cascade in the shape of a horseshoe on the Willamette River. Sallie Tisdale, Harper's magazine, "Catechism of the Waters," 10 June 2019 The water is then piped to nearby wells, where the scientists inject it into the basalt rock 3,300 feet under the ground. Andrew Daniels, Popular Mechanics, "Iceland’s Radical Plan to Slow Climate Change," 9 May 2019 Like many Hawaiian volcanoes, Kilauea is made of basalt, a type of lava that flows very easily. Author: Sarah Kaplan, Anchorage Daily News, "What’s happening inside Hawaii’s Kilauea, the world’s longest-erupting volcano," 4 May 2018 Many residents of affluent Jefferson County say the jobs are not worth burning 84 tons of coal each day by a foreign manufacturer that wants to turn basalt, olivine sand and bauxite into super-efficient insulation. Patricia Sullivan, Washington Post, "Insulation plant divides community in West Virginia," 9 June 2019 If that idea proves correct, the person presenting an offering to the gods in the final, central panel may be the same person buried in the large basalt sarcophagus found in the tomb. Kiona N. Smith, Ars Technica, "Ancient “comic strip” depicts the founding of a Roman city," 10 Oct. 2018 Like many other Hawaiian volcanoes, Kilauea is a shield volcano that emits fluid basalt lava and is defined by its broad dome shape, rather than a steep peak, like Washington’s Mount St. Helens. Lyndsey Matthews, Popular Mechanics, "The Wild 35-Year History of Hawaii's Constantly Erupting Volcano," 16 May 2018 Ludovico Sergardi, who oversaw public works at Saint Peter’s Basilica, helped introduce the beveled black basalt cobblestones, known as sampietrini, which are central to the city’s charm. Jason Horowitz, New York Times, "All Roads Lead to Rome, Where Potholes Will Destroy Your Tires," 25 Mar. 2018

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

1601, in the meaning defined above

History and Etymology for basalt

Latin basaltes, manuscript variant of basanites touchstone, from Greek basanitēs (lithos), from basanos touchstone, from Egyptian bḫnw

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Statistics for basalt

Last Updated

9 Jul 2019

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Time Traveler for basalt

The first known use of basalt was in 1601

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More Definitions for basalt



English Language Learners Definition of basalt

: a type of dark gray to black rock

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More from Merriam-Webster on basalt

Rhyming Dictionary: Words that rhyme with basalt

Spanish Central: Translation of basalt

Nglish: Translation of basalt for Spanish Speakers Encyclopedia article about basalt

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