po·​rous | \ ˈpȯr-əs How to pronounce porous (audio) \

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 Portland regained a four-goal lead in the 69th minute on a clinical run through a porous Kansas City defense. oregonlive, 14 May 2022 The Chargers addressed their porous run defense with the signings of Sebastian Joseph-Day and Austin Johnson. Eddie Brown, San Diego Union-Tribune, 27 Apr. 2022 Overshadowed by either a porous defense or a nonexistent offense — or, on certain nights, by both — the Diamondbacks’ starters have been quietly dominant, regularly holding opposing lineups in check into the middle innings. Nick Piecoro, The Arizona Republic, 26 Apr. 2022 The result has been the league’s second-worst record, a porous defense, and slew of injuries to young players. Gary Washburn, BostonGlobe.com, 26 Mar. 2022 The Lakers’ porous defense allowed the Wizards to make 56.5% of their shots in the third and 63.2% in the fourth. Broderick Turner Staff Writer, Los Angeles Times, 20 Mar. 2022 Despite some porous defense by the Jazz in the first quarter resulting in an inexplicable 42 points from the Kings, JC kept Utah close by dropping in 14 himself on 5 of 6 shooting. Eric Walden, The Salt Lake Tribune, 13 Mar. 2022 But the furious rally was undone by the same porous defense that landed Michigan in a deficit to begin with. Michael Cohen, Detroit Free Press, 27 Feb. 2022 In eastern Afghanistan, many feared that the carnage of the recent airstrikes was the beginning of a violent new chapter of the long-running conflict in the tribal lands that spill across the porous border. New York Times, 30 Apr. 2022 See More

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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Time Traveler for porous

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

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Dictionary Entries Near porous



porous cell

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Last Updated

22 May 2022

Cite this Entry

“Porous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/porous. Accessed 25 May. 2022.

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More Definitions for porous


po·​rous | \ ˈpȯr-əs How to pronounce porous (audio) \

Kids Definition of porous

1 : full of small holes porous wood
2 : capable of absorbing liquids porous paper


po·​rous | \ ˈpōr-əs, ˈpȯr- How to pronounce porous (audio) \

Medical Definition of porous

1 : possessing or full of pores porous bones
2 : permeable to fluids

More from Merriam-Webster on porous

Nglish: Translation of porous for Spanish Speakers

Britannica English: Translation of porous for Arabic Speakers


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