Regolith
/ˈrɛɡ.ə.lɪθ/noun
A layer of loose, unconsolidated rock and dust covering solid bedrock, especially on the Moon or other planetary bodies.
Did you know?Regolith was coined in the late 19th century from Greek roots, and it became a key word in lunar science because Apollo astronauts were walking on a layer of shattered rock, not solid ground.
Etymological Timeline
Late 19th Century
English
regolith
“A loose mantle of rock debris covering solid bedrock or the surface of another body”
1860s
Scientific Latin/English
regolith
“A newly coined geological term for surface rock debris”
Greek
Greek
lithos
“stone, rock”
Greek
Greek
rēgos
“blanket, covering”
Modern English
English
regolith
“The loose outer layer of broken rock and dust on a planetary surface”
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