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impenetrable

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adjective im·pen·e·tra·ble \(ˌ)im-ˈpe-nə-trə-bəl\

Simple Definition of impenetrable

  • : impossible to pass or see through

  • : impossible to understand

Full Definition of impenetrable

  1. 1 a :  incapable of being penetrated or pierced b :  inaccessible to knowledge, reason, or sympathy :  impervious

  2. 2 :  incapable of being comprehended :  inscrutable

im·pen·e·tra·bly play \-blē\ adverb

Examples of impenetrable

  1. The fort's defenses were thought to be impenetrable.

  2. <the ancient temple was surrounded by vast stretches of impenetrable jungle>



Origin of impenetrable

Middle English impenetrabel, from Middle French impenetrable, from Latin impenetrabilis, from in- + penetrabilis penetrable


First Known Use: 15th century


IMPENETRABLE Defined for Kids

impenetrable

play
adjective im·pen·e·tra·ble \im-ˈpe-nə-trə-bəl\

Definition of impenetrable

  1. 1 :  impossible to pass through or see through <impenetrable walls> <impenetrable darkness>

  2. 2 :  impossible to understand <an impenetrable mystery>





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