chalk
A soft, white, powdery limestone (calcium carbonate, CaCO3).
Example
“chalk cliffs are not recommended for climbing”
Other meanings
A piece of chalk, or nowadays processed compressed gypsum (calcium sulfate, CaSO4), that is used for drawing and for writing on a blackboard (chalkboard).
Tailor's chalk.
A kind of
- calcite
Word history
From Old English "ċealc".
Where this comes from
This definition is adapted from “chalk” on Wiktionary, by its contributors; related-word lists use Open English WordNet (CC BY 4.0, based on Princeton WordNet), published under CC BY-SA 4.0. This page is published under the same licence.