3
pressure-tight(adjective, tight, proof, impervious, hermetic)
3
proof(adjective, tight, impervious, hermetic)
3
seaworthy
3
solid
3
staunch
2
flawless
2
hermetically sealed
2
impenetrable(adjective, fast, short, unaffected, unyielding)
2
impregnable
2
incontrovertible
2
inviolable
2
ironclad
2
irrefutable
2
retentive(adjective, tight, proof, impervious, hermetic)
2
right(adjective, precise, accurate)
2
stormproof
2
strong
2
windproof
1
air-locked(adjective, tight, proof, impervious, hermetic)
1
air-proof(adjective, tight, proof, impervious, hermetic)
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APASmart Define. (2015). watertight thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/watertight/thesaurus/synonyms
ChicagoSmart Define. 2015. "watertight thesaurus" https://smartdefine.org/watertight/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2015, watertight thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/watertight/thesaurus/synonyms>.
MLASmart Define. "watertight thesaurus" 13 April 2015. Web. 26 September 2026. <https://smartdefine.org/watertight/thesaurus/synonyms>