Rockwell hardness

Rock·​well hardness | \ ˈräˌkwel-, -kwəl- \

Definition of Rockwell hardness

: the hardness of a metal or alloy measured by an apparatus in which a diamond-pointed cone is pressed into the metal to a standard depth to determine the relative resistance to penetration as indicated automatically by a number on a dial

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

History and Etymology for Rockwell hardness

after Stanley P. Rockwell, 20th century American metallurgist

Learn More About Rockwell hardness

Dictionary Entries Near Rockwell hardness


Rockwell hardness

rock whiting

See More Nearby Entries 

Statistics for Rockwell hardness

Cite this Entry

“Rockwell hardness.” Dictionary, Merriam-Webster, Accessed 7 Dec. 2021.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon


Test Your Vocabulary

Farm Idioms Quiz

  • cow coming home
  • What does 'poke' refer to in the expression 'pig in a poke'?
True or False

Test your knowledge - and maybe learn something along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!