impervious
adjective
im·per·vi·ous
(ˌ)im-ˈpər-vē-əs 
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
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
The superfluid still rubs against the bucket, but the material is totally impervious to friction until the container reaches a certain rotational speed.
—Quanta Magazine, 6 Nov. 2024
This was somewhat fortuitous as the new Soviet T-34 tanks acquired by Ho Chi Minh and the Viet Minh were impervious to the M20 Recoilless Rifle and the Vespa TAP would not have fared well in the jungles of Vietnam.
—Mike Hanlon, New Atlas, 12 Oct. 2024
In South America, China, Russia, and Iran are providing military, economic, and diplomatic support to Nicolás Maduro’s authoritarian government in Venezuela, reinforcing his conviction that his regime is impervious to pressure.
—Antony J. Blinken, Foreign Affairs, 1 Oct. 2024
Waterproof materials are impervious to water, providing a complete barrier, while water-resistant materials only resist water penetration to a certain degree before the water seeps through.
—Sophie Flaxman, Better Homes & Gardens, 26 Sep. 2024
See all Example Sentences for impervious 
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Quanta Magazine, 6 Nov. 2024
This was somewhat fortuitous as the new Soviet T-34 tanks acquired by Ho Chi Minh and the Viet Minh were impervious to the M20 Recoilless Rifle and the Vespa TAP would not have fared well in the jungles of Vietnam.
—Mike Hanlon, New Atlas, 12 Oct. 2024
In South America, China, Russia, and Iran are providing military, economic, and diplomatic support to Nicolás Maduro’s authoritarian government in Venezuela, reinforcing his conviction that his regime is impervious to pressure.
—Antony J. Blinken, Foreign Affairs, 1 Oct. 2024
Waterproof materials are impervious to water, providing a complete barrier, while water-resistant materials only resist water penetration to a certain degree before the water seeps through.
—Sophie Flaxman, Better Homes & Gardens, 26 Sep. 2024
See all Example Sentences for impervious
Dictionary Entries Near impervious
Cite this Entry
“Impervious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/impervious. Accessed 22 Nov. 2024.
Copy CitationKids Definition
impervious
adjective
im·per·vi·ous
(ˈ)im-ˈpər-vē-əs
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
: not allowing entrance or passage
medication packaged in a container impervious to air and light
imperviousness
noun
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