porous

adjective

po·​rous ˈpȯr-əs How to pronounce porous (audio)
Synonyms of porous
1
a
: possessing or full of pores
b
: containing vessels
hardwood is porous
2
a
: permeable to fluids
b
: permeable to outside influences
3
: capable of being penetrated
porous national boundaries
porously adverb
porousness noun

Synonyms of porous

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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The electrode is built from a two-dimensional conductive metal-organic framework (MOF), a porous material made by connecting metal components with organic molecules. — Neetika Walter, Interesting Engineering, 20 Aug. 2026 Wood is a naturally porous material that bends and expands with changes in temperature and moisture. — Jessica Safavimehr, Southern Living, 20 Aug. 2026 Because the levee is earthen and porous, nearly 100 volunteers remained in Rocky Ripple on Sunday afternoon. — Bradley Hohulin, IndyStar, 17 Aug. 2026 Because it’s made of porous material — usually a powdered mix of water, lime, cement and sometimes sand — grout is susceptible to many problems. — Bestreviews, Mercury News, 14 Aug. 2026 See All Example Sentences for porous

Word History

First Known Use

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

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

Phrases Containing porous

Rhymes for porous

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Browse Nearby Words

porosity
porous
porous cell
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Cite this Entry

“Porous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/porous. Accessed 25 Aug. 2026.

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Kids Definition

porous

adjective
po·​rous ˈpōr-əs How to pronounce porous (audio)
ˈpȯr-
1
: full of pores
2
: capable of absorbing liquids

Medical Definition

porous

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

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