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 The city is built on highly porous rock, limestone that’s almost like Swiss cheese. Matt Simon, Wired, "Not to Ruin the Super Bowl, But the Sea Is Consuming Miami," 31 Jan. 2020 Shesterkin was getting a crash course in the Rangers’ bugaboo, a porous defense, a weakness that is not always a problem because of their high-scoring star, Artemi Panarin. Allan Kreda, New York Times, "A Great Goaltending Hope Arrives With a Win," 8 Jan. 2020 With Kemba Walker still out with an illness, the Celtics scuffled against a porous Washington defense that entered the night allowing a league-worst 120.9 points per game. Adam Himmelsbach, BostonGlobe.com, "Celtics get taste of bad medicine and other observations from loss to Wizards," 6 Jan. 2020 Winston should produce another big day for the Buccaneers (6-7) against the Lions’ porous defense. oregonlive, "Detroit Lions vs Tampa Bay Buccaneers: Live score updates, TV channel, how to watch free live stream online," 15 Dec. 2019 The answer may help explain the behavior of natural gases that are trapped in porous rocks. Fox News, "Student solves a decades-old physics mystery," 10 Dec. 2019 The Rockets will be able to take full advantage of the Spurs’ porous defense and could approach their 158-point output from Saturday. Esten Mclaren, USA TODAY Sportsbook Wire, "Houston Rockets at San Antonio Spurs odds, picks and best bets," 3 Dec. 2019 It is then pumped underground into porous basalt rock, mineralizing in about two years — significantly faster than other carbon-capture and storage methods. NBC News, "How to save a glacier: Iceland's scientists offer hope with carbon capture technology," 19 Sep. 2019 Surveillance aircraft, much like those destroyed in the attack, are valuable assets, especially in Africa, where extremist groups seek to exploit the vast expanses and porous borders to avoid detection. New York Times, "Chaos as Militants Overran Airfield, Killing 3 Americans in Kenya," 22 Jan. 2020

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

Time Traveler

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

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Statistics for porous

Last Updated

9 Feb 2020

Cite this Entry

“Porous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/porous. Accessed 20 Feb. 2020.

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More Definitions for porous


How to pronounce porous (audio)

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 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

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More from Merriam-Webster on porous

Thesaurus: All synonyms and antonyms for porous

Rhyming Dictionary: Words that rhyme with porous

Spanish Central: Translation of porous

Nglish: Translation of porous for Spanish Speakers

Britannica English: Translation of porous for Arabic Speakers

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