impenetrable.
Not penetrable.
Meaning & usage
Not penetrable.
The fortress is impenetrable, so it cannot be taken.
Opaque; obscure; not translucent or transparent.
Incomprehensible; fathomless; inscrutable.
Business jargon makes this document impenetrable—I can’t understand it.
Where this word comes from
From Middle English inpenetrabel, inpenetrabyle, from Middle French impenetrable or directly from its etymon, Latin impenetrābilis. By surface analysis, im- + penetrable.
A person not openly given to friendship.
Where this word comes from
From Middle English inpenetrabel, inpenetrabyle, from Middle French impenetrable or directly from its etymon, Latin impenetrābilis. By surface analysis, im- + penetrable.
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Definitions, grammatical labels, IPA, etymology and examples: Wiktionary contributors, extracted by Kaikki / Wiktextract. Adapted under CC BY-SA 4.0. Selected fields and authored examples are shown; third-party quotations and audio are omitted. See contributor history.
Last enriched 2026-09-10. Definitions are in English. Romanizations are shown when supplied by the source; syllable estimates are omitted for unsupported scripts.