32
permanence(noun, support, control, strength, balance)
14
harshness(noun, power, abuse, easy, difficulty)
14
rigidity(noun, easy, condition, discipline, firmness)
14
severity(noun, power, abuse, easy, difficulty)
12
callousness(noun, cruelty, insensitivity, coldness, impenitence)
12
rigor(noun, easy, condition, discipline, firmness)
12
stiffness(noun, firmness, protection, severity, security)
11
toughness(noun, support, control, power, strength)
10
austerity(noun, easy, condition, discipline, firmness)
9
firmness(noun, support, control, change, strength)
9
rigorousness(noun, easy, condition, discipline, firmness)
9
rigour
9
solidity(noun, support, control, strength, balance)
8
difficulty(noun, difficulty, discipline, severity, harshness)
8
inclemency(noun, severity, harshness, conformity, strictness)
8
strength(noun, support, control, change, continue)
8
unfeelingness(noun, cruelty)
7
callosity
7
roughness(noun, power, difficulty, violence, severity)
6
arduousness(noun, difficulty, discipline, toughness, strictness)
<1234510>
11 years ago|10k views|share |citing 
APASmart Define. (2015). hardness thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/hardness/thesaurus/synonyms
ChicagoSmart Define. 2015. "hardness thesaurus" https://smartdefine.org/hardness/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2015, hardness thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/hardness/thesaurus/synonyms>.
MLASmart Define. "hardness thesaurus" 14 April 2015. Web. 21 September 2026. <https://smartdefine.org/hardness/thesaurus/synonyms>