impenetrable
/ɪmˈpɛnətɹəbəl/ adjective, noun
Forms impenetrables inpenetrable
- adjective Not penetrable. “The fortress is impenetrable, so it cannot be taken.”
- adjective Opaque; obscure; not translucent or transparent.
- adjective (figuratively) Incomprehensible; fathomless; inscrutable. “Business jargon makes this document impenetrable—I can’t understand it.”
- noun A person not openly given to friendship.
Synonyms
impermeable impregnable unfathomable abstruse Chinese dense enigmatic fathomless bottomless Greek inapprehensible incognizable incomprehensible ineffable inenubilable inexplicable insensible inscrutable insoluble insolvable heavy
Antonyms
penetrable permeable pregnable fathomable apprehensible clear limpid comprehensible explainable explicable explicatable graspable
Etymology
From Middle English inpenetrabel, inpenetrabyle, from Middle French impenetrable or directly from its etymon, Latin impenetrābilis. By surface analysis, im- + penetrable.
Webster’s 1913
- adjective Incapable of being penetrated or pierced; not admitting the passage of other bodies; not to be entered; impervious; as, an impenetrable shield.
- adjective Having the property of preventing any other substance from occupying the same space at the same time.
Etymology [L. impenetrabilis; pref. im- not + penetrabilis penetrable: cf. F. impénétrable.]
Sources: Wiktionary · WordNet 3.0 · Webster’s 1913 — from the Wiktionary entry “impenetrable”, CC BY-SA 4.0. Details