A really fast thesaurus... with lots of synonyms.
Impenetrable has 109 synonyms. The top synonyms for impenetrable are heavy, thick, impermeable, hard, massive, gluey, serried, nonporous and 101 more. Another word for impenetrable is heavy. Browse the full list below.
| Length
| Random | DefinitionA common synonym for impenetrable is heavy. Other synonyms include thick, impermeable, hard, massive.
Impenetrable has 109 synonyms listed on Thesaurasize.
(adj): not penetrable Example: "the fortress is impenetrable, so it cannot be taken."
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