clast

noun

ˈklast How to pronounce clast (audio)
: a fragment of rock

Examples of clast 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.
Water was then added, creating a chemical reaction that produced heat and trapped the lime clasts in the concrete. — Taylor Nicioli, CNN Money, 19 Dec. 2025 Meanwhile, an identical chunk of concrete without the lime-clast structure never healed, and the water just kept flowing through the sample. — Daniel Cusick, Scientific American, 18 Jan. 2023 The clasts can then react with water, producing a solution saturated with calcium. — Jennifer Ouellette, ArsTechnica, 30 July 2025 The presolar silicate grains inside the clasts contained significant amounts of the isotope Carbon-13. — Elizabeth Rayne, Ars Technica, 2 Aug. 2023 See All Example Sentences for clast

Word History

Etymology

probably back-formation from clastic

First Known Use

1952, in the meaning defined above

Time Traveler
The first known use of clast was in 1952

Rhymes for clast

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Browse Nearby Words

classy
clast
clastic
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Cite this Entry

“Clast.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/clast. Accessed 7 Jul. 2026.

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More from Merriam-Webster on clast

Britannica.com: Encyclopedia article about clast

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