ba·​salt | \bə-ˈsȯlt, ˈbā-ˌsȯlt \

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 \ adjective

Examples of basalt in a Sentence

Recent Examples on the Web

In the living room, the vintage chair is by Illum Wikkelsø, and the mantel and stone benches are both of local basalt. Gisela Williams, ELLE Decor, "A Portuguese Family Manor is Transformed Into a Heritage-Rich Island Getaway," 17 Sep. 2018 Majestic subarctic mountains, white snow, black basalt, and teal oceans with breaching whales. Kathleen Renda, House Beautiful, "This Icelandic Apartment Is Filled With Small-Space Inspiration," 16 Aug. 2018 The Giant's Causeway is comprised of around 40,000 interlocking basalt columns that resemble a footpath. David Grossman, Popular Mechanics, "Scientists Uncover the Secret of Strange, Geometrical Rock Formations," 12 Apr. 2018 Ask the front desk to arrange an excursion into the waters around Filicudi with a local; don’t miss La Canna rock (trips from $25), a basalt tower rising from the sea that is said to possess magical powers. Howie Kahn, Smithsonian, "These Volcanic, Italian Islands Have Been Beloved by Travelers Since Homeric Times," 11 July 2018 But some scientists look at the basalt-rich lava fields around Kilauea, which could yet produce more explosions in coming days, and see something else: a portal to Mars, whose surface is mostly composed of basaltic rocks. Mike Ives, New York Times, "Kilauea Volcano’s Lava Fields Offer Scientists a Portal to Mars," 28 May 2018 They're formed from basalt lava and have become smooth over time. Liz Dufour, USA TODAY, "WOW Air stopover: Photos of 82 hours in Iceland," 25 May 2018 Starting in February 2015, his team dug about 20 test pits, unearthing modern debris, colonial porcelain, and, finally, the basalt slabs of a Mexica period floor. Lizzie Wade, Science | AAAS, "Feeding the gods: Hundreds of skulls reveal massive scale of human sacrifice in Aztec capital," 21 June 2018 The acres of raw, blocky basalt look as fresh as the flows shown spilling from Kilauea on the nightly news. Mare Czinar, azcentral, "Volcanoes in Arizona: Sunset Crater hike shows off eruption's aftermath," 12 June 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

12 Nov 2018

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Time Traveler for basalt

The first known use of basalt was in 1601

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English Language Learners Definition of basalt

: a type of dark gray to black rock

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Comments on basalt

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by force of circumstances

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