32 entries under proof topic. ×

15
hermetic(verb, adjective, tight, closed)
10
sealed(adjective, tight, impervious, hermetic)
9
tight(adjective, impervious, hermetic, sealed)
9
watertight(adjective, tight, impervious, hermetic)
8
air-tight(adjective, tight, impervious, hermetic)
7
impermeable(adjective, tight, impervious, impenetrable)
7
waterproof(adjective, water, tight, impervious)
5
gas-tight(adjective, tight, impervious, hermetic)
4
airproof(adjective, tight, impervious, hermetic)
4
hermetical(adjective, tight, impervious, hermetic)
3
dampproof(adjective, tight, impervious, hermetic)
3
gastight(adjective, tight, impervious, hermetic)
3
pressure-tight(adjective, tight, impervious, hermetic)
2
enclosed(adjective, tight, impervious, hermetic)
2
pressurized(adjective, tight, impervious, hermetic)
2
tightly sealed(expression, adjective, idiom, tight)
1
air-locked(adjective, tight, impervious, hermetic)
1
air-proof(adjective, tight, impervious, hermetic)
1
gas proof(adjective, tight, impervious, hermetic)
1
hermetically-impervious(adjective, tight, impervious, hermetic)
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APASmart Define. (2015). airtight thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/airtight/thesaurus/synonyms
ChicagoSmart Define. 2015. "airtight thesaurus" https://smartdefine.org/airtight/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, airtight thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/airtight/thesaurus/synonyms>.
MLASmart Define. "airtight thesaurus" 14 April 2015. Web. 24 September 2026. <https://smartdefine.org/airtight/thesaurus/synonyms>