Synonyms|101Antonyms|52|Broader|0Narrower|0Related|43
1
formidably(adverb, invulnerably)
1
gravely
1
grievously
1
hazily(adverb, opaquely)
1
heavily
1
hermetically
1
impassably
1
impenetrable
1
inaccessibly
1
inconceivably
1
inexplicably
1
leadenly
1
murkily(adverb, opaquely)
1
perplexingly
1
tightly
1
unassailably
1
unbeatably(adverb, invulnerably)
1
unintelligibly
1
unknowably
0
aimlessly
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APASmart Define. (2013). impenetrably thesaurus. Retrieved September 25, 2026, from https://smartdefine.org/impenetrably/thesaurus/synonyms
ChicagoSmart Define. 2013. "impenetrably thesaurus" https://smartdefine.org/impenetrably/thesaurus/synonyms (accessed September 25, 2026).
HarvardSmart Define 2013, impenetrably thesaurus, Smart Define, viewed 25 September, 2026, <https://smartdefine.org/impenetrably/thesaurus/synonyms>.
MLASmart Define. "impenetrably thesaurus" 17 June 2013. Web. 25 September 2026. <https://smartdefine.org/impenetrably/thesaurus/synonyms>