0
firm(difficult, cold, indifferent, troubled, inflexible)
0
hard as nails(expression, adjective, idiom, hard, impassive)
0
hardboiled
0
hardened(hard, insensitive, unsusceptible)
0
hardhearted(hard, insensitive, unsusceptible)
0
icebox
0
immune to(expression, adjective, dead, insensitive, insusceptible)
0
impasses
0
imperceptive(adjective, hard, impassive, insensitive, unsusceptible)
0
impercipient
0
imperturbable
0
impervious to(expression, adjective, dead, insensitive, insusceptible)
0
inactive(adjective, dull, quiet, flat, heavy)
0
incurious(hard, insensitive, unsusceptible)
0
inert(adjective, dull, quiet, flat, heavy)
0
inhospitableness
0
inviolable
0
invulnerable
0
languid(adjective, dull, quiet, flat, heavy)
0
lumpy(adjective, dull, quiet, flat, heavy)
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APASmart Define. (2015). impassible thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/impassible/thesaurus/synonyms
ChicagoSmart Define. 2015. "impassible thesaurus" https://smartdefine.org/impassible/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2015, impassible thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/impassible/thesaurus/synonyms>.
MLASmart Define. "impassible thesaurus" 14 April 2015. Web. 26 September 2026. <https://smartdefine.org/impassible/thesaurus/synonyms>