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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Authorities are urging visitors to stop jamming pocket change between the basalt columns that make up the Giant’s Causeway, a national nature reserve and UNESCO World Heritage Site on the coast of the North Atlantic Ocean. Sarah Kuta, Smithsonian Magazine, 4 June 2025 Ancient Tools Show Our Ancestors Ate a Varied Diet For the study, scientists examined maces and anvils made from basalt, a type of rock formed from rapidly cooling lava at the Earth’s surface, that ancient humans used to crack and crush plant foods. Tom Gavin, EverydayHealth.com, 13 Jan. 2025 The lower level is rich in basalt, while the upper level contains a lot of silica. Paul Smaglik, Discover Magazine, 3 Jan. 2025 In addition to steatite, sedimentary stones and basalt were also carved for pipes. Matthew Wills, JSTOR Daily, 14 June 2025 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 6 Jul. 2025.

Kids Definition

basalt

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

More from Merriam-Webster on basalt

Last Updated: - Updated example sentences
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