impervious

adjective

im·​per·​vi·​ous (ˌ)im-ˈpər-vē-əs How to pronounce impervious (audio)
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
imperviously adverb
imperviousness noun

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."

Examples of impervious in a Sentence

He looked at her, impervious to her tears … Jean Stafford, Children Are Bored on Sunday, (1945) 1953
… the trunk … is encased in so hard a bark, as to be almost impervious to a bullet … Herman Melville, Omoo, 1847
… Berlin struck me, above all, as impervious to any political reactions whatever … Stephen Spender, New York Times Magazine, 30 Oct.1977
the material for this coat is supposed to be impervious to rain the rain forest is impervious to all but the most dedicated explorers
Recent Examples on the Web But the Fountain has not been impervious to the storm of post-pandemic challenges. Charles McNulty, Los Angeles Times, 5 Mar. 2024 More cities are also adopting stormwater fees, charging landowners based on the amount of impervious surfaces on a property, thus encouraging them to open up more ground. Matt Simon, WIRED, 29 Feb. 2024 Stereo vision sensors are well-equipped to meet regulatory requirements on dark roads and in low-visibility weather and are impervious to vibration on bumpy roads. Leaf Jiang, Forbes, 29 Feb. 2024 His support has remained stubbornly impervious to an endless parade of things that would have killed any other politician’s career. Dan McLaughlin, National Review, 18 Jan. 2024 As long as Powell remains chair, the Fed is almost certain to remain impervious to political interference. Jeff Stein, Washington Post, 7 Jan. 2024 Some containing chromium among other constituents, such as nickel and molybdenum, are more corrosion-resistant than others, forming an impervious and protective molecular-scale surface barrier of chromium oxide. Carlton Reid, WIRED, 16 Feb. 2024 And widespread use of doxycycline as a preventive measure could — theoretically — contribute to mutations that make bacteria impervious to the drug. Mike Stobbe, Fortune Well, 2 Oct. 2023 Cities have more impervious surfaces and are sprawling outward with roadways, rooftops, and parking lots. Justine Calma, The Verge, 29 Sep. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'impervious.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Latin impervius, from in- + pervius pervious

First Known Use

1615, in the meaning defined at sense 1a

Time Traveler
The first known use of impervious was in 1615

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Dictionary Entries Near impervious

Cite this Entry

“Impervious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/impervious. Accessed 29 Mar. 2024.

Kids Definition

impervious

adjective
im·​per·​vi·​ous (ˈ)im-ˈpər-vē-əs How to pronounce impervious (audio)
1
: not letting something enter or pass through
a coat impervious to rain
2
: not disturbed or upset
impervious to criticism
imperviousness noun

Medical Definition

impervious

adjective
im·​per·​vi·​ous (ˈ)im-ˈpər-vē-əs How to pronounce impervious (audio)
: not allowing entrance or passage
medication packaged in a container impervious to air and light
imperviousness noun

More from Merriam-Webster on impervious

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