Definition of impenetrable
1a : incapable of being penetrated or piercedb : inaccessible to knowledge, reason, or sympathy : impervious
2 : incapable of being comprehended : inscrutable
From the M-W Editors
Examples of impenetrable in a Sentence
The fort's defenses were thought to be impenetrable.
the ancient temple was surrounded by vast stretches of impenetrable jungle
Origin and Etymology of impenetrable
Middle English impenetrabel, from Middle French impenetrable, from Latin impenetrabilis, from in- + penetrabilis penetrable
First Known Use: 15th century
IMPENETRABLE Defined for English Language Learners
impenetrable
playDefinition of impenetrable for English Language Learners
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: impossible to pass or see through
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: impossible to understand
IMPENETRABLE Defined for Kids
impenetrable
playDefinition of impenetrable for Students
1 : impossible to pass through or see through impenetrable walls impenetrable darkness
2 : impossible to understand an impenetrable mystery
Learn More about impenetrable
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Thesaurus: All synonyms and antonyms for impenetrable Spanish Central: Translation of impenetrable Nglish: Translation of impenetrable for Spanish speakers Britannica English: Translation of impenetrable for Arabic speakers
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