hardness
The quality of being hard.
Other meanings
An instance of this quality; hardship.
The quantity of calcium carbonate dissolved in water, usually expressed in parts per million (ppm).
Related words
- hardness of hearing
- Knoop hardness
- macrohardness
- microhardness
- nanohardness
- total hardness
- Vickers hardness
- water hardness
Word history
From Old English "heardnes".
Where this comes from
This definition is adapted from “hardness” on Wiktionary, by its contributors, published under CC BY-SA 4.0. This page is published under the same licence.