1
imperceptive(adjective, hard, indifferent, unkind, unresponsive)
1
impersuadable
1
impersuasible
1
imperturbable
1
impervious to(expression, adjective, dead, insensitive, insusceptible)
1
incapable
1
incommutable
1
inconvertible
1
incurious(adjective, hard, indifferent, unkind, unresponsive)
1
indefeasible
1
indurated(adjective, hard, careless, indifferent, cruel)
1
inert
1
insensate(noun, adjective, hard, careless, indifferent)
1
insusceptible of change(expression, idiom)
1
intransmutable
1
inured(noun, adjective, hard, careless, indifferent)
1
invariable
1
irresponsible(adjective, safe, unaffected, protected, resistant)
1
irretrievable
1
irreversible
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APASmart Define. (2015). unsusceptible thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/unsusceptible/thesaurus/synonyms
ChicagoSmart Define. 2015. "unsusceptible thesaurus" https://smartdefine.org/unsusceptible/thesaurus/synonyms (accessed September 29, 2026).
HarvardSmart Define 2015, unsusceptible thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/unsusceptible/thesaurus/synonyms>.
MLASmart Define. "unsusceptible thesaurus" 14 April 2015. Web. 29 September 2026. <https://smartdefine.org/unsusceptible/thesaurus/synonyms>