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

Local institutions — already facing shortages of foreign currency and tight liquidity — must raise capital to finance such a sale, but MTN expects the transaction to close by year-end.

— Tiisetso Motsoeneng, semafor.com, 24 Aug. 2026
Graham Nordone and Norman are locked in a tight contest, according to polls.

— Naomi Lim, The Washington Examiner, 24 Aug. 2026

Definition of tight

Adjective

Autumn Joy Stonecrop Also called autumn joy sedum, this hardy, summer- and fall-flowering perennial is known for its succulent foliage and dense clusters of tiny pink flowers.

— Alexandra Jones, The Spruce, 30 Aug. 2026
There was less consensus about the dust kicked up from the playa, which can be dense enough to cause whiteouts.

— Henry Alford, New Yorker, 29 Aug. 2026

Definition of dense

Adjective

Even during the rut, Infalt shoots most of his mature bucks in the thick stuff near where deer sleep.

— Josh Honeycutt, Outdoor Life, 27 Aug. 2026
The evidence suggests that back then a thicker, ancient atmosphere sheltered flowing streams and sparkling lakes.

— Ashwin R. Vasavada, The Conversation, 27 Aug. 2026

Definition of thick

Adjective

California Cruise is even closer than expected, with deliveries slated to begin next year.

— New Atlas, New Atlas, 30 Aug. 2026
The success of this trial was possible through the close and constructive cooperation between the participating German Air Force organisations, the exercise management team and the expert teams from Rheinmetall Air Defence and Hensoldt.

— Prabhat Ranjan Mishra, Interesting Engineering, 30 Aug. 2026

Definition of close

Adjective

Child safety experts lauded the settlement and the accompanying pressure campaign as a giant leap forward in the effort to regulate an industry that until this year appeared all but impenetrable to reform, either from the courts or legislatures.

— Sonja Sharp, Los Angeles Times, 29 Aug. 2026
The space offers guests a rare glimpse into a facet of Japanese nightlife that can feel impenetrable to outsiders.

— Condé Nast, Condé Nast Traveler, 26 Aug. 2026

Definition of impenetrable

Adjective

Roads can become impassable, evacuation orders can change and homes or outdoor enclosures can be damaged, leaving pets vulnerable to injury or escape.

— Melanie Marshall, San Diego Union-Tribune, 21 Aug. 2026
But challenges remain, including impassable roads, the presence of armed groups and the movement of people displaced by violence.

— ABC News, ABC News, 19 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 31 Aug. 2026.

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Synonyms of impermeable

adjective

Example Sentences

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