impenetrable

adjective im·pen·e·tra·ble \ (ˌ)im-ˈpe-nə-trə-bəl \
Updated on: 8 Nov 2017

Definition of impenetrable

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

impenetrably

play \(ˌ)im-ˈpe-nə-trə-blē\ adverb

Examples of impenetrable in a Sentence

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

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

Recent Examples of impenetrable from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'impenetrable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of impenetrable

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


IMPENETRABLE Defined for English Language Learners

impenetrable

adjective

Definition of impenetrable for English Language Learners

  • : impossible to pass or see through

  • : impossible to understand


IMPENETRABLE Defined for Kids

impenetrable

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

Definition of impenetrable for Students

1 :impossible to pass through or see through
  • impenetrable walls
  • impenetrable darkness
2 :impossible to understand
  • an impenetrable mystery


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