hard·​ness | \ ˈhärd-nəs How to pronounce hardness (audio) \

Definition of hardness

1 : the quality or state of being hard
2a : 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

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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 hardness from 150 ppm to 250 ppm (parts per million). Danielle Beurteaux, Popular Mechanics, "How to Get Your Swimming Pool Ready for Summer," 18 May 2018 Besides their sought-after clarity, extreme hardness, and entanglement in civil wars, diamonds tell unique geologic stories. Scott K. Johnson, Ars Technica, "Blue diamonds come from ocean floor that is pushed nearly to Earth’s core," 1 Aug. 2018 Graded to an incredibly high 62+ Rockwell hardness, these knives are also fully stain- and rust-resistant, and are precision-balanced and weighted for superior performance. Popular Mechanics, "These Precise Japanese Knives Are a Kitchen Must-Have," 11 Dec. 2018 First, components are designed in thousands of different materials and alloys for reasons of performance (hardness, resistance to corrosion, etc.). WSJ, "While Great, 3-D Printers Have Limitations," 2 Nov. 2018 Adjust the calcium hardness by using calcium chloride. Danielle Beurteaux, Popular Mechanics, "How to Get Your Swimming Pool Ready for Summer," 18 May 2018 This is directly dependent on the hardness of the water. Danielle Beurteaux, Popular Mechanics, "How to Get Your Swimming Pool Ready for Summer," 18 May 2018 More intimate than a typical period drama, the movie becomes an unexpectedly intense, racking examination of Mary’s psychology: her impulsiveness, her defiance, the almost frightening hardness at her core. Jamie Hawkesworth, Vogue, "Saoirse Ronan on Growing Up on Camera, the Changing Politics of Ireland, and Becoming a Queen," 11 July 2018 And while the cast (which also includes Melissa Miller in dual roles) is uniformly strong, the blend of hardness and heartbreak that Meaney displays is especially affecting. James Hebert, sandiegouniontribune.com, "A struggle to cling to identity is at heart of La Jolla Playhouse's quietly moving 'Queens'," 10 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hardness.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of hardness

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

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Statistics for hardness

Last Updated

14 Mar 2019

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Time Traveler for hardness

The first known use of hardness was before the 12th century

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English Language Learners Definition of hardness

: the quality or state of being hard

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Comments on hardness

What made you want to look up hardness? Please tell us where you read or heard it (including the quote, if possible).


having no equal

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