adjective im·per·vi·ous \ (ˌ)im-ˈpər-vē-əs \
|Updated on: 21 Jun 2018

Definition of impervious

1 a : not allowing entrance or passage : impenetrable
  • a coat impervious to rain
b : not capable of being damaged or harmed
  • a carpet impervious to rough treatment
2 : not capable of being affected or disturbed
  • impervious to criticism





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Examples of impervious in a Sentence

  1. He looked at her, impervious to her tears … —Jean StaffordChildren Are Bored on Sunday(1945) 1953
  2. … the trunk … is encased in so hard a bark, as to be almost impervious to a bullet … —Herman MelvilleOmoo1847
  3. … Berlin struck me, above all, as impervious to any political reactions whatever … —Stephen SpenderNew York Times Magazine30 Oct.1977
  4. the material for this coat is supposed to be impervious to rain

  5. the rain forest is impervious to all but the most dedicated explorers

Recent Examples of impervious from the Web

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

Did You Know?

The English language is far from impervious, and, of course, a great many Latinate terms have entered it throughout its history. Impervious is one of the many that broke through in the 17th century. It comes from the Latin impervius, which adds the prefix im- to pervius, meaning "passable" or "penetrable." Pervius-which is also the source of the relatively uncommon English word pervious, meaning "accessible" or "permeable"-comes from per-, meaning "through," and via, meaning "way."

Origin and Etymology of impervious

Latin impervius, from in- + pervius pervious

IMPERVIOUS Defined for English Language Learners


Definition of impervious for English Language Learners

  • : not allowing something (such as water or light) to enter or pass through

  • : not bothered or affected by something

IMPERVIOUS Defined for Kids


adjective im·per·vi·ous \ im-ˈpər-vē-əs \

Definition of impervious for Students

1 : not letting something enter or pass through
  • The coat is impervious to rain.
2 : not bothered or affected by something
  • He's impervious to their criticism.

Medical Dictionary


adjective im·per·vi·ous \ (ˈ)im-ˈpər-vē-əs \

medical Definition of impervious

: not allowing entrance or passage
  • medication packaged in a container impervious to air and light



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a figure representing a hated person

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