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

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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 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 The outer layer hardened and became impermeable. — Catherina Gioino, Fortune, 11 Apr. 2026 Oil and gas infuse the pores of sandstone; layers of impermeable caprock trap it inside. — Jeffrey Marlow, New Yorker, 5 Apr. 2026 See All Example Sentences for impermeable

Recent Examples of Synonyms for impermeable

Adjective

The problem is… their opponents will likely be France, a team that looks impervious.

— Carl Anka, New York Times, 4 July 2026
Overloading Your Washer Even the softest of towels are not impervious to improper laundering, and overloading your washer or using too little water can affect how thoroughly the towels are washed.

— Louise Parks, Martha Stewart, 30 June 2026

Definition of impervious

Adjective

Slots and gates are valuable in congested airports like LaGuardia because tight airspace restrictions and crowded airports in a big city like New York cap airline growth.

— Leslie Josephs, CNBC, 20 July 2026
Her tight smile squeezes tiny tears into the corners of her eyes.

— Literary Hub, Literary Hub, 20 July 2026

Definition of tight

Adjective

At the same time, the bath shouldn’t be tucked so deeply into dense landscaping that predators can hide nearby.

— Jessica Safavimehr, Southern Living, 18 July 2026
With consistent use, many people also notice that regrowing hair becomes finer and less dense, making epilators an appealing alternative for anyone looking to stretch the time between hair removal sessions.

— Iman Balagam, Vogue, 17 July 2026

Definition of dense

Adjective

And that’s a lot of energy to shed as a vehicle comes blaring back into Earth’s thick atmosphere, a process that typically annihilates objects returning from space unless they are precisely designed to survive the trip.

— Jackie Wattles, CNN Money, 16 July 2026
The water drew back from the house, left a thick, stinking silt across the floor.

— Literary Hub, Literary Hub, 16 July 2026

Definition of thick

Adjective

The play was a no-call, but Clark took exception to the physicality and yelled at the closest official.

— James Boyd, New York Times, 19 July 2026
The carrier is flying about 6,500 flights per day this year — nearly an entire Alaska Airlines more worth of travel more than its closest competitor, according to Cirium — yet American’s profit gap has grown.

— Leslie Josephs, CNBC, 19 July 2026

Definition of close

Adjective

The Trojans kill the messenger, then haul the horse past their walled city’s impenetrable gates.

— Hillary Busis, Vanity Fair, 15 July 2026
The Athletic’s Tomas Hill Lopez-Menchero breaks down Spain’s impenetrable defense, while Cerys Jones analyzes whether Kylian Mbappe can guide France to a third consecutive World Cup final.

— The Athletic, New York Times, 15 July 2026

Definition of impenetrable

Adjective

After spending the offseason dedicating himself to succeeding in the weight room, a visibly stronger Richard was an impassable brick wall against the summer league guards.

— Joseph Dycus, Mercury News, 17 July 2026
RickyRay Robertson said floodwaters rose so quickly that roads became impassable within minutes, forcing him and his neighbor to abandon her vehicle and wade through chest-deep water to safety.

— Diego Mendoza, CNN Money, 16 July 2026

Definition of impassable

Adjective

Playing on home soil in a venue that has become an almost impregnable fortress, El Tri will face England in the Round of 16 — in what is arguably the most important match in Mexican soccer history.

— Carlos Rodriguez, Chicago Tribune, 5 July 2026
Alexander the Great conquered it in 332 BCE after building a causeway to what had been considered an impregnable island fortress.

— Jane Arraf, NPR, 23 June 2026

Definition of impregnable

Browse Nearby Words

impermanent

impermeable

impermissible

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“Impermeable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/impermeable. Accessed 23 Jul. 2026.

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Synonyms of impermeable

adjective

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