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

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Other Words from impermeable

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

Examples of impermeable in a Sentence

an impermeable layer of rock a fabric impermeable to moisture
Recent Examples on the Web This may be most obvious in how his costume has changed throughout the decades, from a cloth suit to an impermeable combat gear in films like Christopher Nolan’s Dark Knight trilogy. Theo Karasavvas, Ars Technica, "How modern tech has powered our favorite superheroes through the years," 4 Jan. 2020 Gas will be affordable long-term Thanks to fracking, which releases fossil fuels from hitherto impermeable shale rock, American gas is so abundant that producers can’t find enough domestic demand and are rushing to export. Kevin Crowley,, "Big Oil Prepares to Defend Big Gas as Climate Week Begins," 22 Sep. 2019 The new law augurs well for Denver, a city whose open space to population ratio is shrinking, whose ozone levels and incidences of lung disease are rising, and whose impermeable concrete surfaces are increasing. Wellington Webb, The Denver Post, "Webb: Park Hill Golf Course land can and must be preserved under new conservation law," 12 Nov. 2019 From 2001 to 2014, the slabs expanded in area by about 25,000 square miles, forming an impermeable barrier the size of West Virginia that prevents meltwater from trickling down through the ice. National Geographic, "Something strange is happening to Greenland's ice sheet," 18 Sep. 2019 The Chiefs probably are the best team in the NFL right now and the Ravens showed on Sunday that their defense is not impermeable. Baltimore Sun Staff,, "Ravens vs. Chiefs staff picks: Who will win Sunday’s rematch in Kansas City?," 18 Sep. 2019 Miles is a Brit, from the fringe of Birmingham, with an accent of impermeable glumness. Anthony Lane, The New Yorker, "Boys Will Be Boys in “Ford v Ferrari”," 8 Nov. 2019 Prior to that, scientists thought the sub-sea permafrost was essentially an impermeable barrier keeping methane at bay. Ryan Prior, CNN, "Russian scientists say they've found the highest-ever 'flares' of methane in Arctic waters," 12 Oct. 2019 Between the aquifer layers are impermeable capping layers. Scott K. Johnson, Ars Technica, "Jakarta has sunk by up to 4 meters, forcing Indonesia to build a new capital," 27 Aug. 2019

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.

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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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Time Traveler for impermeable

Time Traveler

The first known use of impermeable was in 1661

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Statistics for impermeable

Last Updated

23 Jan 2020

Cite this Entry

“Impermeable.” Dictionary, Merriam-Webster, Accessed 18 Feb. 2020.

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More Definitions for impermeable


How to pronounce impermeable (audio)

English Language Learners Definition of impermeable

technical : not allowing something (such as a liquid) to pass through


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 impermeability (audio) \ noun, plural impermeabilities

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