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

VentriGel provides a porous and fibrous structure for new cells to latch onto, Christman said. San Diego Union-Tribune, "Heart attack treatment gel shows safety in early human study," 16 Sep. 2019 And, while it hasn’t been eulogized with the same fanfare as the other formative HBO dramas, to my eye, Six Feet Under’s vision of a diverse and porous postnuclear family is unrivaled in both prescience and earned sentiment. Adam Wilson, Harper's magazine, "Good Bad Bad Good," 16 Sep. 2019 Ng and La Frenierre are investigating a possible explanation: that some of the meltwater from Chimborazo's glaciers doesn't drain directly into streams but instead percolates down into the porous volcanic rock at the base of the ice. Tim Appenzeller, Science | AAAS, "Global warming has made iconic Andean peak unrecognizable," 11 Sep. 2019 Each man had a single bedroom, so to create community out of these single rooms, students were organized into houses, formed vertically off of a staircase in a porous arrangement sometimes called the staircase or entryway plan. Carla Yanni, Smithsonian, "How College Dorms Evolved to Fit America’s Gender and Racial Politics," 6 Sep. 2019 The run defense, porous as any in FBS last season, was no better Friday night, as the Cowboys ran for 352 yards and averaged nearly seven yards per play. oregonlive, "Oregon State long on belief, short on performance as Oklahoma State routs Beavers 52-36," 31 Aug. 2019 The firm, but bouncy porous bread helps soak up the cheese, said executive chef Meghan Levins. Savannah Eadens, The Courier-Journal, "Beer + cheese. Everything you've ever wanted to know about the Kentucky concoction," 26 Aug. 2019 Either way, Jones and Smith should be able to help the Terps improve their own porous run defense as well as get to opposing quarterbacks. Don Markus, baltimoresun.com, "Maryland’s 11 most important players heading into the 2019 football season," 23 Aug. 2019 Millions of gallons of water rushed through the porous limestone, and the Boars had to flee to an elevated rock 2½ miles from the mouth of the cave. Max Marshall, SI.com, "Mining the Miracle," 26 June 2019

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

5 Oct 2019

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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 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

Rhyming Dictionary: Words that rhyme with porous

Thesaurus: All synonyms and antonyms for porous

Spanish Central: Translation of porous

Nglish: Translation of porous for Spanish Speakers

Britannica English: Translation of porous for Arabic Speakers

Comments on porous

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a bell tower

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