Definition of 'hardness'

Noun

1. the property of being rigid and resistant to pressure; not easily scratched; measured on Mohs scale
      Antonyms: softness
2. devoid of passion or feeling; hardheartedness
      Synonyms: unfeelingness callousness callosity insensibility
3. the quality of being difficult to do; "he assigned a series of problems of increasing hardness"; "the ruggedness of his exams caused half the class to fail"
      Synonyms: ruggedness
4. excessive sternness; "severity of character"; "the harshness of his punishment was inhuman"; "the rigors of boot camp"
      Synonyms: severity severeness harshness rigor rigour rigorousness rigourousness inclemency stiffness

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