32 entries under proof topic. ×

10
waterproof(adjective, water, tight, impervious)
9
tight(adjective, impervious, hermetic, sealed)
9
hermetic(adjective, tight, impervious, airtight)
8
impermeable(adjective, tight, impervious, impenetrable)
7
airtight(adjective, tight, impervious, hermetic)
7
sealed(adjective, tight, impervious, hermetic)
3
dampproof(adjective, tight, impervious, hermetic)
3
gastight(adjective, tight, impervious, hermetic)
3
hermetical(adjective, tight, impervious, hermetic)
3
pressure-tight(adjective, tight, impervious, hermetic)
2
retentive(adjective, tight, impervious, hermetic)
1
air-locked(adjective, tight, impervious, hermetic)
1
air-proof(adjective, tight, impervious, hermetic)
1
air-tight(adjective, tight, impervious, hermetic)
1
airproof(adjective, tight, impervious, hermetic)
1
enclosed(adjective, tight, impervious, hermetic)
1
gas-tight(adjective, tight, impervious, hermetic)
1
gas proof(adjective, tight, impervious, hermetic)
1
hermetically-impervious(adjective, tight, impervious, hermetic)
1
hermetically-sealed(adjective, tight, impervious, hermetic)
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APASmart Define. (2015). watertight thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/watertight/thesaurus/synonyms
ChicagoSmart Define. 2015. "watertight thesaurus" https://smartdefine.org/watertight/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, watertight thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/watertight/thesaurus/synonyms>.
MLASmart Define. "watertight thesaurus" 13 April 2015. Web. 24 September 2026. <https://smartdefine.org/watertight/thesaurus/synonyms>