1. [ noun ] the quality of being difficult to do

"he assigned a series of problems of increasing hardness"

Related terms: difficulty
2. [ noun ] devoid of passion or feeling
Synonyms: callousness insensibility unfeelingness
Related terms: insensitivity
3. [ noun ] the property of being rigid and resistant to pressure; not easily scratched; measured on Mohs scale
Related terms: softness consistency firmness incompressibility soft hard
4. [ noun ] excessive sternness
Synonyms: harshness inclemency stiffness rigor rigour severity

"severity of character" "the harshness of his punishment was inhuman" "the rigors of boot camp"

Related terms: sternness
Similar spelling:   hardiness