151 entries under adjective topic. ×

10
impenetrable
4
impermeable(tight, impervious, hermetic)
3
airtight(tight, impervious, hermetic)
3
bombproof
3
dampproof(tight, impervious, hermetic)
3
hermetic(tight, impervious)
3
insusceptible(resist, resistant)
3
pressure-tight(tight, impervious, hermetic)
3
protective
3
resistive(resist, resistant)
3
unsusceptible(resist, resistant)
3
waterproof(tight, impervious, hermetic)
3
watertight(tight, impervious, hermetic)
2
callous(calm, restrained, unconcerned, subdued)
2
diagnostic
2
dull
2
gritty
2
obtuse
2
tempered
2
tough
10 years ago|17k views|share |citing 
APASmart Define. (2015). proof thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/proof/thesaurus/synonyms
ChicagoSmart Define. 2015. "proof thesaurus" https://smartdefine.org/proof/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, proof thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/proof/thesaurus/synonyms>.
MLASmart Define. "proof thesaurus" 22 December 2015. Web. 22 September 2026. <https://smartdefine.org/proof/thesaurus/synonyms>