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

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 Spartans’ defense remains porous against the pass, as does the Buckeyes’. Chris Solari, Detroit Free Press, 15 Nov. 2021 But as productive as the Bulldogs’ offense has been, Samford’s defense has been equally porous. Mark Inabinett | Minabinett@al.com, al, 13 Nov. 2021 Instead of being mushy, porous plastic filled with air, they are actually made of hard material and filled with small glass spheres, each containing air. Matt Simon, Wired, 12 Nov. 2021 Craig, 52, remembers when the border was so porous that her kids would trick-or-treat in two countries on Halloween in Derby Line. Washington Post, 9 Nov. 2021 Jarrod coated the porous wood countertop in water-base clear polyurethane. Sarah Egge, Better Homes & Gardens, 8 Nov. 2021 The offense sputtered with just 3.8 yards per play, while the usually porous defense picked up the slack. Adam Burke Vsin, Los Angeles Times, 8 Nov. 2021 In other words, the Celtics defense has not been awful this season except for a few porous stretches, such as the fourth quarter Monday against the Chicago Bulls. BostonGlobe.com, 6 Nov. 2021 Their running game will come out of hiding against a porous Vikings front, and Lamar Jackson will mix in enough big strikes to get his team back on track. Baltimore Sun Staff, baltimoresun.com, 5 Nov. 2021

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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Dictionary Entries Near porous



porous cell

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Statistics for porous

Last Updated

18 Nov 2021

Cite this Entry

“Porous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/porous. Accessed 26 Nov. 2021.

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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

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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