Added 9 October 2026
impenetrable
/ɪmˈpɛnətɹəbəl/ adjective
In Latin: impenetrābilis, invius Wiktionary
adjective Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about impenetrable at Wordnik → Where our words come from →
-
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.
noun
- A person not openly given to friendship. (clarification of this definition is needed)
Origin
From Middle English inpenetrabel, inpenetrabyle, from Middle French impenetrable or directly from its etymon, Latin impenetrābilis. By surface analysis, im- + penetrable.
From Wiktionary, via Kaikki.org (CC BY-SA)