Definition

A layer of loose material, like soil or rock, that covers the solid rock beneath it on the surface of the Earth, Moon, or other planets.

Example

The regolith on the Moon is made up of fine dust and rocky debris.

Conversation

Did you know that the moon's surface is covered in regolith?

Really? I always thought it was just rock.

Yeah, it’s actually loose material that sits on top of the bedrock.

That makes sense! It must be interesting to study.

Synonyms & Antonyms

Root Explanation

Regolith is formed from "rego-" (from Greek "rhegma", meaning to break or to flow) and "lithos" (meaning stone). The term refers to the layer of loose, fragmented material that covers solid bedrock, essentially broken stone.

Memory Tip

Think of 'broken' ('rego-') material that is 'stone' ('lithos') — that's what regolith is, a layer of broken stone covering the ground.

Visually Confused Words