im·​per·​me·​able | \ (ˌ)im-ˈpər-mē-ə-bəl How to pronounce impermeable (audio) \

Definition of impermeable

: not permitting passage (as of a fluid) through its substance broadly : impervious

Other Words from impermeable

impermeability \ (ˌ)im-​ˌpər-​mē-​ə-​ˈbi-​lə-​tē How to pronounce impermeable (audio) \ noun

Examples of impermeable in a Sentence

an impermeable layer of rock a fabric impermeable to moisture
Recent Examples on the Web They’re structured with layers upon layers of cooling wires, heavy metal rings, an impermeable outer shell, utility gauges and instruments. Carolyn Giardina, The Hollywood Reporter, 21 Apr. 2022 Its goal: prove that the sandstone layers can hold carbon, and that the cap rock just above them is impermeable enough to keep it from escaping. Christa Case Bryant, The Christian Science Monitor, 15 Apr. 2022 If the pandemic has shown us anything about work life and home life, it’s that the two aren’t separate spheres, divided by an impermeable wall. Cassie Werber, Quartz, 25 Feb. 2022 Once closer to the surface, the hot water often ran into a cap of impermeable volcanic deposits. John Timmer, Ars Technica, 23 Mar. 2022 Eventually what remains is the impermeable underbelly, such as shale or granite. Erica Gies, Scientific American, 16 Mar. 2022 Americans are living in two different countries right now, and the border between those countries is impermeable. Roxane Gay, New York Times, 28 Jan. 2022 But no number of boosts can be expected to make bodies totally impermeable to infection. Sarah Zhang, The Atlantic, 23 Dec. 2021 For an accumulation to form, a rare set of conditions needs to be in place: a porous rock that holds the gas in and an impermeable capstone to prevent it from continuing upwards. William Ralston, Wired, 16 Dec. 2021 See More

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

First Known Use of impermeable

1661, in the meaning defined above

History and Etymology for impermeable

Late Latin impermeabilis, from Latin in- + Late Latin permeabilis permeable

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The first known use of impermeable was in 1661

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Last Updated

9 May 2022

Cite this Entry

“Impermeable.” Dictionary, Merriam-Webster, Accessed 21 May. 2022.

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More Definitions for impermeable


im·​per·​me·​able | \ (ˈ)im-ˈpər-mē-ə-bəl How to pronounce impermeable (audio) \

Medical Definition of impermeable

: not permitting passage (as of a fluid) through its substance the plasma membrane of a red blood cell is relatively impermeable to sodium and calcium ions

Other Words from impermeable

impermeability \ (ˌ)im-​ˌpər-​mē-​ə-​ˈbil-​ət-​ē How to pronounce impermeable (audio) \ noun, plural impermeabilities

More from Merriam-Webster on impermeable

Nglish: Translation of impermeable for Spanish Speakers

Britannica English: Translation of impermeable for Arabic Speakers


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