Synonyms|713Antonyms|152|Broader|9Narrower|8Related|663
2
viscous
2
watertight(adjective, fast, short, unaffected, unyielding)
1
Delphic(adjective, incomprehensible)
1
abnormal(obscure, dark, superior, mysterious, supernatural)
1
accustomed(adjective, hard, unfeeling, unsympathetic, prepared)
1
alchemistic
1
anagogic(supernatural, spiritual, mystical)
1
astrological
1
benumbed(adjective, hard, unfeeling, unsympathetic, prepared)
1
beyond reach
1
beyond understanding
1
big
1
bigot
1
blocked
1
blurred
1
bulletproof(adjective, dense)
1
caked(adjective, set, solid, heavy, deep)
1
case-hardened(adjective, hard, unfeeling, unsympathetic, prepared)
1
celestial(obscure, dark, superior, mysterious, supernatural)
1
clabbered(adjective, set, solid, heavy, deep)
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APASmart Define. (2015). impenetrable thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/impenetrable/thesaurus/synonyms
ChicagoSmart Define. 2015. "impenetrable thesaurus" https://smartdefine.org/impenetrable/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2015, impenetrable thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/impenetrable/thesaurus/synonyms>.
MLASmart Define. "impenetrable thesaurus" 10 April 2015. Web. 23 September 2026. <https://smartdefine.org/impenetrable/thesaurus/synonyms>