hardness

noun

hard·​ness ˈhärd-nəs 

1

: the quality or state of being hard

2

a

: the cohesion of the particles on the surface of a mineral as determined by its capacity to scratch another or be itself scratched compare mohs' scale

b

: resistance of metal to indentation under a static load or to scratching

Synonyms

• adversity
• asperity
• difficulty
• hardship
• rigor

Examples of hardness in a Sentence

the hardness of a diamond

The wood's hardness makes it suitable for carving.

Recent Examples on the Web

Calcium is instrumental for developing strong bones and teeth, supplying both structure and hardness to your physical architecture. —Caroline Tien, SELF, 19 Feb. 2025

In oil, heat diffuses more slowly, resulting in a moderate hardness, and the process is less likely to damage the sword. —Kevin Chroust, Outside Online, 5 Feb. 2025

The level of water hardness will vary based on your water supply. —Brittany Vanderbill, Better Homes & Gardens, 26 Nov. 2024

The experience leans more cool than comfy: There are warnings about the heat upstairs during certain months and the hardness of the futons. —Kim Velsey, Curbed, 19 July 2024

Word History

First Known Use

before the 12th century, in the meaning defined at sense 1

Phrases Containing hardness

• Brinell hardness
• Brinell hardness number

Kids Definition

hardness

noun

hard·​ness ˈhärd-nəs 

1

: the quality or state of being hard

2

: the ability of a substance (as a mineral) to scratch another substance or be itself scratched