8 entries under impassable topic. ×

2
mystic(adjective, solid, dense, psychic, clairvoyant)
1
Delphic(solid, dense, unfathomable, impenetrable, unintelligible)
1
baffling(solid, dense, unfathomable, impenetrable, unintelligible)
1
incognizable(solid, dense, unfathomable, impenetrable, unintelligible)
1
ungraspable(solid, dense, unfathomable, impenetrable, unintelligible)
1
unknowable(solid, dense, unfathomable, impenetrable, unintelligible)
0
enigmatical(solid, dense, unfathomable, unintelligible)
0
indiscernible(solid, dense, unfathomable, unintelligible)
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APASmart Define. (2015). sibylline thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/sibylline/thesaurus/synonyms
ChicagoSmart Define. 2015. "sibylline thesaurus" https://smartdefine.org/sibylline/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, sibylline thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/sibylline/thesaurus/synonyms>.
MLASmart Define. "sibylline thesaurus" 14 April 2015. Web. 24 September 2026. <https://smartdefine.org/sibylline/thesaurus/synonyms>