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
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.
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 Cleaning up the regolith and turning it into something viable wouldn’t be easy. Sven Bilén, Discover Magazine, 17 July 2024 With its last vestiges of battery charge, the lander will record the lunar sunset and a phenomenon last observed during the final Apollo mission, in which magnetic forces agitate the regolith across the surface as the sun fades behind the horizon. Josh Dinner, Space.com, 31 Jan. 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

Dictionary Entries Near regolith

Cite this Entry

“Regolith.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/regolith. Accessed 21 Feb. 2025.

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