po·rous | \ ˈpȯr-əs \

Definition of porous 

1a : possessing or full of pores

b : containing vessels hardwood is porous

2a : permeable to fluids

b : permeable to outside influences

3 : capable of being penetrated porous national boundaries

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Other words from porous

porously adverb
porousness noun

Examples of porous in a Sentence

The country has a porous border. a cleaner that should not be used on porous surfaces

Recent Examples on the Web

Fracking, short for hydraulic fracturing, uses enormous quantities of water, which drillers pressurize and shoot deep below the surface to help separate shale oil from porous rocks. Jay Root, star-telegram, "New Mexico official: Texans are 'stealing' water and selling it back for fracking," 7 June 2018 Finley picked apart Louisville’s defense last season, throwing for 367 yards on just 31 attempts and showing how porous that defense was. Jake Lourim, The Courier-Journal, "How Louisville football can (and can't) beat NC State," 12 July 2018 Hipsters and anyone else coveting the porous, soft-tipped luxury of badger-hair shaving brushes may be among the commenters, as the bristles also made the list published by the U.S. Trade Representative's office. Dave Mccombs And Andrew Hobbs, chicagotribune.com, "Badger hair, bull semen, MSG among products on Trump's China tariff list," 11 July 2018 The Diamondbacks’ defense was porous, failing to convert as many as five would-be outs in those five innings. Nick Piecoro, azcentral, "David Peralta’s blast lifts Diamondbacks past Rockies," 10 July 2018 They are built with non-porous materials and are veterinarian approved. Natalie Dreier, ajc, "Cool dogs: Company develops air conditioned public dog houses for dogs on the go," 7 July 2018 These MOFs are solid but porous materials with enormous surface areas—an MOF the size of sugar cube can have the internal surface area as big as many football fields. Emily Matchar, Smithsonian, "This Device Pulls Water Out of Desert Air," 20 June 2018 The boundary between public and private is porous in an epic chronicling the dark days of the AIDS epidemics in Ronald Reagan's America. Charles Mcnulty, latimes.com, "For the Berkeley Rep revival of 'Angels in America,' the play is the thing," 29 May 2018 The Cavs have lost 10 of 13 games and are porous defensively. cleveland.com, "Eight questions (and some answers) about the slumping Cavs as the trade deadline nears," 24 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'porous.' 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 porous

14th century, in the meaning defined at sense 1a

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Statistics for porous

Last Updated

24 Aug 2018

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Time Traveler for porous

The first known use of porous was in the 14th century

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More Definitions for porous



English Language Learners Definition of porous

: having small holes that allow air or liquid to pass through

: easy to pass or get through


po·rous | \ ˈpȯr-əs \

Kids Definition of porous

1 : full of small holes porous wood

2 : capable of absorbing liquids porous paper


po·rous | \ ˈpōr-əs, ˈpȯr- \

Medical Definition of porous 

1 : possessing or full of pores porous bones

2 : permeable to fluids

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Comments on porous

What made you want to look up porous? Please tell us where you read or heard it (including the quote, if possible).


alleviating pain or harshness

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