porosity

noun

po·​ros·​i·​ty pə-ˈrä-sə-tē How to pronounce porosity (audio)
pȯ-
plural porosities
1
a
: the quality or state of being porous
b
: the ratio of the volume of interstices of a material to the volume of its mass
2
: pore

Examples of porosity in a Sentence

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.
Some of the amine groups hang out solo, while others link with each other to help create the porosity within the solid. — ArsTechnica, 8 June 2026 Then there’s density (how many strands per square inch) and porosity (how readily hair absorbs moisture). — Allison Palmer, Miami Herald, 26 Mar. 2026 All these factors combined make this one a great pick for low-porosity hair, which craves hydration but can easily be weighed down by the thicker oils and rich formulas. — Eden Stuart, Glamour, 7 July 2026 The bursts break apart the biomass structure, increase porosity, and accelerate carbonization. — Aamir Khollam, Interesting Engineering, 19 June 2026 See All Example Sentences for porosity

Word History

First Known Use

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

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

Rhymes for porosity

See All Rhymes for porosity

Browse Nearby Words

porosimeter
porosity
porous
See all Nearby Words

Cite this Entry

“Porosity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/porosity. Accessed 10 Jul. 2026.

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Kids Definition

porosity

noun
po·​ros·​i·​ty pə-ˈräs-ət-ē How to pronounce porosity (audio)
pōr-ˈäs-, 
pȯ-ˈräs-
plural porosities
: the quality or state of being porous

Medical Definition

porosity

noun
po·​ros·​i·​ty pə-ˈräs-ət-ē, pō-, pȯ- How to pronounce porosity (audio)
plural porosities
1
a
: the quality or state of being porous
b
: the ratio of the volume of interstices of a material to the volume of its mass
2
: pore

More from Merriam-Webster on porosity

Britannica.com: Encyclopedia article about porosity

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