basalt

noun

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

Examples of basalt in a Sentence

Recent Examples on the Web
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The material combines recycled PETG with basalt fiber reinforcement. Kaif Shaikh, Interesting Engineering, 26 May 2026 The new method described in the paper, however, uses silicate rocks like basalt as the main ingredient, which are turned into cement electrochemically rather than through heat, which uses less energy. Alex Knapp, Forbes.com, 18 May 2026 While there is a variety of soil types throughout the vineyard, the high quantities of rock including fractured basalt help with both drainage and water retention at depth, and large deposits of iron and manganese add to the wine’s minerality. Mike Desimone, Robb Report, 17 May 2026 The interesting thing is that, according to thermodynamics, the chemical conversion of basalt minerals to calcium oxide only requires around half as much as the conversion from limestone. Scott K. Johnson, ArsTechnica, 15 May 2026 See All Example Sentences for basalt

Word History

Etymology

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

First Known Use

1601, in the meaning defined above

Time Traveler
The first known use of basalt was in 1601

Browse Nearby Words

Cite this Entry

“Basalt.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/basalt. Accessed 31 May. 2026.

Kids Definition

basalt

noun
: a dark gray to black usually fine-grained igneous rock
basaltic adjective

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