IMPERMEABLE Synonyms: 51 Similar and Opposite Words

impermeable

adjective

(ˌ)im-ˈpər-mē-ə-bəl

Definition of impermeable

as in impervious

impossible to get through or into the wall of security people surrounding the rock band was impermeable

Synonyms & Similar Words

Relevance

Antonyms & Near Antonyms

as in tight

not allowing penetration (as by gas, liquid, or light) an impermeable seal on the ancient tomb had preserved the artifacts exceptionally well

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

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.

Recent Examples of impermeable Engineers eventually replaced them with a version made up of 20 impermeable compartments of high-pressure hoses containing water. — Mack Degeurin, Popular Science, 18 June 2026 Dry waterproofing technology, which is basically like an invisible, impermeable sock liner. — Olivia Young, Travel + Leisure, 29 May 2026 The spongy material is mostly made of air, yet nearly impermeable to both air and liquid. — Brandee Gruener, Southern Living, 29 Apr. 2026 When a finger contacts an impermeable surface, sweat pores within the ridges release moisture that plasticizes the skin’s keratin layer, which increases friction in turn. — Scott Travers, Forbes.com, 14 Apr. 2026 See All Example Sentences for impermeable

Recent Examples of Synonyms for impermeable

Adjective

This brand makes impervious base layers with a chemical-free blend of nylon and lycra.

— Olivia Young, Travel + Leisure, 13 Aug. 2026
To deal with the settling, Peters and his team developed flexible flooring lined with an impervious three-ply fabric.

— Jennifer Tucker, The Conversation, 7 Aug. 2026

Definition of impervious

Adjective

Elevated on an all-wood frame and ringed by tall evergreens, the home feels like a slice of Lake Tahoe in the middle of a dense suburb.

— David Caraccio, Sacbee.com, 15 Aug. 2026
They are being sculpted by intense radiation from nearby young stars, while new stars are forming inside the dense clouds.

— Kaif Shaikh, Interesting Engineering, 15 Aug. 2026

Definition of dense

Adjective

Swathes of those still standing are marked for death, their fate written like braille in the form of scores of tiny holes — no thicker than a dot left by a ballpoint pen — beneath the bark.

— Jack Bantock, CNN Money, 13 Aug. 2026
Eastern handles are shorter and thicker, catering more to those who use a Penhold grip, where the head of the paddle is facing down and the paddle is held like a pen.

— BestReviews, Chicago Tribune, 13 Aug. 2026

Definition of thick

Adjective

This is something the First Alert Weather Team will keep a close eye on throughout the week.

— Michael Autovino, CBS News, 17 Aug. 2026
Makhachev’s record-setting victory came over Ian Machado Garry via unanimous decision (49-46, 49-46, 48-47) in one of Makhachev’s closest fights.

— Mark Puleo, New York Times, 16 Aug. 2026

Definition of close

Adjective

The rule also failed to tackle all of the ways trusts and other vehicles provide impenetrable secrecy for the wealthy and the crooked alike.

— Casey Michel, The Atlantic, 14 Aug. 2026
Cody erects impenetrable emotional walls around him that deny him from asking for help and creating community.

— Randy Myers, Mercury News, 12 Aug. 2026

Definition of impenetrable

Adjective

Poor and sometimes impassable roads can also make remote areas difficult to reach, while insecurity restricts where health workers can safely operate.

— ABC News, ABC News, 15 Aug. 2026
Duneland schools remain closed due to outages throughout its buildings, numerous impassable roads and downed power lines throughout the community, according to the district website.

— Carole Carlson, Chicago Tribune, 15 Aug. 2026

Definition of impassable

Adjective

Dropped catches from Steve Smith, Green and Travis Head ensured yesterday's brief rally in the field fizzled out and allowed Bangladesh to bat itself into an almost impregnable position.

— ABC News, ABC News, 14 Aug. 2026
The shell of a good- sized adult abalone is more or less impregnable to most of the kelp forest’s predators, too strong and too thick for penetration.

— Literary Hub, Literary Hub, 29 July 2026

Definition of impregnable

Browse Nearby Words

impermanent

impermeable

impermissible

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Cite this Entry

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“Impermeable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/impermeable. Accessed 21 Aug. 2026.

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Synonyms of impermeable

adjective

Example Sentences

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