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

Example Sentences

Recent Examples on the Web Instead of just reaching the moon, the United States and China want to mine it, laying claim to the water that exists in the form of ice and other precious resources, such as metals and even oxygen stored in the lunar regolith. Christian Davenport, Washington Post, 14 Jan. 2023 Outgassing from active volcanoes may have also deposited water onto the lunar regolith. Katrina Miller, WIRED, 13 Dec. 2022 And what better place to take off and land from than the giant litter box that is the undisturbed regolith of the Moon? Kyle Hill, Discover Magazine, 5 Nov. 2013 The real surprise was that the plants, stunted and stressed from growing in regolith, grew at all. Stephen Ornes, Discover Magazine, 23 Dec. 2022 It is made of algae grown in tanks filled with water that would be harvested by melting ice found in the Martian regolith (sandy soil). Evan Fraser, CNN, 7 Oct. 2022 When the Apollo astronauts landed on the moon, lunar regolith was discovered to be sharp enough to tear tiny holes in their spacesuits. Ashley Strickland, CNN, 7 Dec. 2022 One of the CubeSats will make seven orbits of the moon, scanning its surface for the presence of water ice in the lunar regolith, or soil, which future lunar astronauts could harvest and use. Jeffrey Kluger, Time, 16 Nov. 2022 To carry out this mission, the rover will carry several scientific instruments, including a regolith and ice drill and multiple spectrometers that can detect hydrogen atoms from water. Sam Zlotnik, Smithsonian Magazine, 2 Nov. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'regolith.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


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.” Dictionary, Merriam-Webster, Accessed 27 Jan. 2023.

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