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noun reg·o·lith \ˈre-gə-ˌlith\

Definition of regolith

  1. :  unconsolidated residual or transported material that overlies the solid rock on the earth, moon, or a planet

Origin and Etymology of regolith

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

First Known Use: 1897

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