1
as in dense
impossible to get through or into
the wall of security people surrounding the rock band was impermeable
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Antonyms & Near Antonyms
2
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
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Antonyms & Near Antonyms
Example Sentences
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Recent Examples of impermeable
The part of Texas that flooded last week is known as Flash Flood Alley because of its impermeable limestone hills and frequent downpours, but these floods were unusually severe for the area.
—
Rebecca Hersher, NPR, 7 July 2025
The spongy material is mostly made of air, yet nearly impermeable to both air and liquid.
—Brandee Gruener, Southern Living, 7 May 2025
Given the area’s especially hard, impermeable soil and the high cost of installing private wastewater systems, many residents have resorted to straight piping to deal with human wastewater.
—Curtis Bunn, NBC news, 1 May 2025
What if the girls all band together and reject me like an impermeable cellular membrane, keeping me out, unable to penetrate their circle of friendship?
—Michael Nied, People.com, 28 Apr. 2025
See All Example Sentences for impermeable
Rebecca Hersher, NPR, 7 July 2025
The spongy material is mostly made of air, yet nearly impermeable to both air and liquid.
—Brandee Gruener, Southern Living, 7 May 2025
Given the area’s especially hard, impermeable soil and the high cost of installing private wastewater systems, many residents have resorted to straight piping to deal with human wastewater.
—Curtis Bunn, NBC news, 1 May 2025
What if the girls all band together and reject me like an impermeable cellular membrane, keeping me out, unable to penetrate their circle of friendship?
—Michael Nied, People.com, 28 Apr. 2025
See All Example Sentences for impermeable
Recent Examples of Synonyms for impermeable
Adjective
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Other valuable fruiting plants include elderberry, spicebush (), and native roses, which produce nutrient-dense hips in fall.—
Maria Azzurra Volpe,
MSNBC Newsweek,
1 Oct. 2025
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Since September 2024, a new federal law requires mammogram reports to state whether breast tissue is dense, and to mention the possibility of additional imaging.—
Dr. Megha Gupta,
ABC News,
1 Oct. 2025
Adjective
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Marcela closed her lips tight and gently shook her head.—
Zuzana Říhová,
Literary Hub,
26 Sep. 2025
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The roughly five-minute sequence is shot in tight close-up on Day-Lewis, who oscillates between anger, pain and gleeful contempt.—
Patrick Ryan,
USA Today,
26 Sep. 2025
Adjective
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But that doesn't mean Davis is impervious to economic headwinds.—
Laura Hackett,
NPR,
26 Sep. 2025
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Broder was a rare figure that was impervious to the notorious agency wars, commanding respect across agency lines.—
Nellie Andreeva,
Deadline,
24 Sep. 2025
Adjective
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Some models suggest that K2-18b is a hycean world — an ocean planet with a thick atmosphere of hydrogen — and the signature of dimethyl sulfide was detected by the James Webb Space Telescope.—
Keith Cooper,
Space.com,
1 Oct. 2025
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Its fabric is thick but not too heavy, according to reviewers, which is great for someone like me whose body temperature fluctuates constantly.—
Melody Kazel,
PEOPLE,
1 Oct. 2025
Adjective
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Others – seemingly those who are non-religious or simply impenetrable by internet theories – quipped at the possibility.—
Melina Khan,
USA Today,
24 Sep. 2025
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Beyond that, however, pollen’s seemingly impenetrable shell—made up of the biopolymer sporopollenin—had long stumped researchers and limited its use.—
Sandy Ong,
JSTOR Daily,
11 Sep. 2025
Adjective
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The storm flooded creeks, toppled trees and washed out roads, especially in Cataloochee Valley, where all trails became impassable.—
Joe Marusak,
Charlotte Observer,
27 Sep. 2025
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The famed route experienced extensive blowdowns, erosion, and landslides, resulting in much of the roadway being impassable after Helene struck in September 2024.—
Graham Hurley,
CNN Money,
21 Sep. 2025
Adjective
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Trump has previously suggested a deal was close.—
Khaleda Rahman,
MSNBC Newsweek,
1 Oct. 2025
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The trainer visits Pegasus daily and is like the horse’s shadow during hospital visits, keeping a close eye to ensure the safety of Pegasus and those around him.—
Miami Herald,
Miami Herald,
30 Sep. 2025
Adjective
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No matter what someone’s day entails, a sturdy tote bag is sure to come in handy.—
L. Daniela Alvarez,
Better Homes & Gardens,
29 Sep. 2025
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If possible, drive to a nearby sturdy building.—
CA Weather Bot,
Sacbee.com,
29 Sep. 2025
Cite this Entry
“Impermeable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/impermeable. Accessed 2 Oct. 2025.
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