semipermeable

adjective

semi·​per·​me·​able ˌse-mē-ˈpər-mē-ə-bəl How to pronounce semipermeable (audio)
ˌse-ˌmī-, 
-mi-
: partially but not freely or wholly permeable
specifically : permeable to some usually small molecules but not to other usually larger particles
a semipermeable membrane
semipermeability
ˌse-mē-ˌpər-mē-ə-ˈbi-lə-tē How to pronounce semipermeable (audio)
ˌse-ˌmī-, 
-mi-
noun

Examples of semipermeable 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.
Nowhere seems to drift through this as through a semipermeable membrane. — David Searcy, Harpers Magazine, 30 Dec. 2025 The science behind this is based on the fact that eggshells are semipermeable, which means air can get through. — Michelle Darrisaw, Southern Living, 10 June 2026 There’s a drainage line at the bottom, often under a semipermeable polymer layer that forms a firm bottom to the bunker and prevents rocks and soil from coming up during freeze-thaw cycles. — Bradley S. Klein, WSJ, 17 June 2022 When sprayed onto fresh produce, Iceborea becomes a natural thin film and a semipermeable barrier that can protect against microorganisms. — Hannah Hall, Washington Post, 9 Jan. 2023 See All Example Sentences for semipermeable

Word History

First Known Use

1888, in the meaning defined above

Time Traveler
The first known use of semipermeable was in 1888

Rhymes for semipermeable

See All Rhymes for semipermeable

Browse Nearby Words

semipermeability
semipermeable
semiplant
See all Nearby Words

Cite this Entry

“Semipermeable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/semipermeable. Accessed 7 Jul. 2026.

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Kids Definition

semipermeable

adjective
semi·​per·​me·​able ˌsem-i-ˈpər-mē-ə-bəl How to pronounce semipermeable (audio)
ˌsem-ˌī-
: partially but not freely or entirely permeable
especially : permeable to some usually small molecules but not to other usually larger particles
semipermeability
-ˌpər-mē-ə-ˈbil-ət-ē How to pronounce semipermeable (audio)
noun

Medical Definition

semipermeable

adjective
semi·​per·​me·​able ˌsem-i-ˈpər-mē-ə-bəl, ˌsem-ˌī- How to pronounce semipermeable (audio)
: partially but not freely or wholly permeable
specifically : permeable to some usually small molecules but not to other usually larger particles
a semipermeable membrane
semipermeability
-ˌpər-mē-ə-ˈbil-ət-ē How to pronounce semipermeable (audio)
noun
plural semipermeabilities
Last Updated: - Updated example sentences
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