impermeable

1 of 2

adjective

im·​per·​me·​able (ˌ)im-ˈpər-mē-ə-bəl How to pronounce impermeable (audio)
Synonyms of impermeablenext
: not permitting passage (as of a fluid) through its substance
broadly : impervious
impermeability
(ˌ)im-ˌpər-mē-ə-ˈbi-lə-tē How to pronounce impermeable (audio)
noun

impermeability

2 of 2

noun

im·​permeability (¦)im How to pronounce impermeability (audio)
əm+
: the quality or state of being impermeable

Synonyms of impermeable

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Adjective

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Examples of impermeable in a Sentence

Adjective an impermeable layer of rock a fabric impermeable to moisture
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.
Adjective
Oil and gas infuse the pores of sandstone; layers of impermeable caprock trap it inside. — Jeffrey Marlow, New Yorker, 5 Apr. 2026 The spongy material is mostly made of air, yet nearly impermeable to both air and liquid. — Brandee Gruener, Southern Living, 29 Apr. 2026 Chocolate brown stripes punctuate a light charcoal gray background, and the low-pile weave made from recycled polyester gives it an impermeable, easy-to-clean surface. — Julia Harrison, Architectural Digest, 26 June 2026 The outer layer hardened and became impermeable. — Catherina Gioino, Fortune, 11 Apr. 2026 See All Example Sentences for impermeable

Word History

Etymology

Adjective

Late Latin impermeabilis, from Latin in- + Late Latin permeabilis permeable

First Known Use

Adjective

1661, in the meaning defined above

Time Traveler
The first known use of impermeable was in 1661

Rhymes for impermeable

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Browse Nearby Words

impermeabilize
impermeable
impermissibility
See all Nearby Words

Cite this Entry

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

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Kids Definition

impermeable

adjective
im·​per·​me·​able (ˈ)im-ˈpər-mē-ə-bəl How to pronounce impermeable (audio)
: not permitting passage (as of a fluid) through the material of which it is made
impermeability
(ˌ)im-ˌpər-mē-ə-ˈbil-ət-ē How to pronounce impermeable (audio)
noun

Medical Definition

impermeable

adjective
im·​per·​me·​able (ˈ)im-ˈpər-mē-ə-bəl How to pronounce impermeable (audio)
: not permitting passage (as of a fluid) through its substance
the plasma membrane of a red blood cell is relatively impermeable to sodium and calcium ions
impermeability
(ˌ)im-ˌpər-mē-ə-ˈbil-ət-ē How to pronounce impermeable (audio)
noun
plural impermeabilities

More from Merriam-Webster on impermeable

Nglish: Translation of impermeable for Spanish Speakers

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