regolith

noun

reg·​o·​lith ˈre-gə-ˌlith How to pronounce regolith (audio)
: unconsolidated residual or transported material that overlies the solid rock on the earth, moon, or a planet

Examples of regolith in a Sentence

Recent Examples on the Web
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The regolith is composed of a variety of minerals, many of which contain oxygen, typically the heavier component of rocket fuel. John Timmer, Ars Technica, 17 Feb. 2025 In which case, the determined billionaires behind SpaceX and Blue Origin might not wait around for NASA, and the next moon boots in the regolith might stamp a corporate logo in the dust. IEEE Spectrum, 8 July 2019 Schwartz added some artificial moondust—regolith—to certain organoid tubes to approximate its impact combined with that of radiation. Dhruv Khullar, The New Yorker, 10 Feb. 2025 Analysis of the sample found volcanic glass beads in the lunar regolith that have been dated to 123 million years ago, give or take 15 million years. Keith Cooper, Space.com, 3 Feb. 2025 See All Example Sentences for regolith

Word History

Etymology

Greek rhēgos blanket + English -lith; akin to Greek rhezein to dye — more at raga

First Known Use

1897, in the meaning defined above

Time Traveler
The first known use of regolith was in 1897

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Cite this Entry

“Regolith.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/regolith. Accessed 10 Mar. 2025.

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