regolith

noun

1. (countable, uncountable)The layer of loose rock, dust, sand, and soil, resting on the bedrock, that constitutes the surface layer of most dry land on Earth, the Moon, and other large solid aggregated celestial objects. Submarine regolith also exists.

   “The structures on the surface were gone from normal view, pulverized into regolith across a span of aeons.”

   “The soil sample, called LZS-1, is the latest in a list of lunar regolith simulants of varying quality that have been developed to help Nasa and other space agencies around the world prepare for missions to the Moon.”