1
impassive(adjective, hard, careless, indifferent, cruel)
1
impenetrable(adjective, hard, unfeeling, unsympathetic, hardened)
1
impenitent(adjective, hard, careless, indifferent, cruel)
1
impious(adjective, hard, unfeeling, unsympathetic, hardened)
1
inaccessible(adjective, hard, unfeeling, unsympathetic, hardened)
1
incrusted
1
indifferent(adjective, hard, careless, cruel, apathetic)
1
indurate
1
inflexible(adjective, hard, careless, indifferent, cruel)
1
insensible(adjective, hard, careless, indifferent, cruel)
1
insentient(adjective, hard, careless, indifferent, cruel)
1
irreverent(adjective, hard, unfeeling, unsympathetic, hardened)
1
lapidified
1
leathery
1
numb
1
obdurate(adjective, hard, careless, indifferent, cruel)
1
obtuse(noun, adjective, hard, unfeeling, unsympathetic)
1
ossified
1
petrified
1
prepared(adjective, hard, unfeeling, unsympathetic, experienced)
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APASmart Define. (2015). toughened thesaurus. Retrieved September 27, 2026, from https://smartdefine.org/toughened/thesaurus/synonyms
ChicagoSmart Define. 2015. "toughened thesaurus" https://smartdefine.org/toughened/thesaurus/synonyms (accessed September 27, 2026).
HarvardSmart Define 2015, toughened thesaurus, Smart Define, viewed 27 September, 2026, <https://smartdefine.org/toughened/thesaurus/synonyms>.
MLASmart Define. "toughened thesaurus" 13 April 2015. Web. 27 September 2026. <https://smartdefine.org/toughened/thesaurus/synonyms>