Earth & SkyGreek → English
Regolith
/ˈrɛɡəlɪθ/noun
The layer of loose dust and broken rock lying over solid bedrock.
The Greek roots
ῥῆγος
rhêgos
blanket, rug
λίθος
líthos
stone
Literally: “blanket of stone”
The story of the word
George P. Merrill coined it in 1897 for the weathered blanket on Earth, a geologist's word for the stuff between soil and rock. Apollo gave it a wider audience: the Moon has regolith too, but ground by micrometeorites rather than by water and frost, so the grains stay jagged. That sharpness chewed through the astronauts' boot seals and glove fingertips within three days.
- How it travelled
- Ancient Greek → scientific coinage → English
- First recorded
- 1897
Same family
monolithlithographyneolithicmegalith
In a sentence
Any Mars base will have to build with regolith, because nothing heavy is coming from Earth.