1
as in dense
impossible to get through or into
the ancient temple was surrounded by vast stretches of impenetrable jungle
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Antonyms & Near Antonyms
2
as in mysterious
being beyond one's powers to know, understand, or explain
the mysteries of that religion are completely impenetrable to outsiders
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3
as in incomprehensible
impossible to understand
the textbook's language is completely impenetrable, at least to me
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4
as in tight
not allowing penetration (as by gas, liquid, or light)
the container of toxic waste has an impenetrable seal to prevent leaks
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Example Sentences
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Recent Examples of impenetrable
But the war has also shown that missile defenses are not impenetrable, with at least seven US service members killed by hostile action.
—
Stephen Clark, ArsTechnica, 25 Apr. 2026
Completed in 1960, its diagrid exterior, clad in Portland stone, sought to blend in with the rest of the upscale Mayfair neighborhood while asserting itself as an impenetrable fortress.
—Rebecca Rose, Travel + Leisure, 24 Apr. 2026
This was one of the city's most impenetrable buildings, surrounded by armed guards, made to look uninviting and unappealing.
—Condé Nast, Condé Nast Traveler, 23 Apr. 2026
Clearly, Villeneuve knows how to turn an impenetrable and famously difficult literary material into something truly cinematic and sweeping.
—Brent Lang, Variety, 15 Apr. 2026
See All Example Sentences for impenetrable
Stephen Clark, ArsTechnica, 25 Apr. 2026
Completed in 1960, its diagrid exterior, clad in Portland stone, sought to blend in with the rest of the upscale Mayfair neighborhood while asserting itself as an impenetrable fortress.
—Rebecca Rose, Travel + Leisure, 24 Apr. 2026
This was one of the city's most impenetrable buildings, surrounded by armed guards, made to look uninviting and unappealing.
—Condé Nast, Condé Nast Traveler, 23 Apr. 2026
Clearly, Villeneuve knows how to turn an impenetrable and famously difficult literary material into something truly cinematic and sweeping.
—Brent Lang, Variety, 15 Apr. 2026
See All Example Sentences for impenetrable
Recent Examples of Synonyms for impenetrable
Adjective
-
Plants form a dense tuft of stiff grass-like foliage.—
Kim Toscano,
Southern Living,
19 May 2026
-
Along the way, the grade grows dramatically, temperatures drop, and the views and climate zones shift from dense forest to alpine tundra.—
Travel + Leisure Editors,
Travel + Leisure,
19 May 2026
Adjective
-
Yoshi's adventure this time around is eponymously mysterious at first glance.—
Will Greenwald,
PC Magazine,
19 May 2026
-
At the same time, a mysterious presence — known only as the Leather Man — and an Army private (Melton) seeks vengeance after his own daughter goes missing.—
Ellise Shafer,
Variety,
19 May 2026
Adjective
-
Europeans, Bennett notes, find this genuinely incomprehensible.—
Nick Lichtenberg,
Fortune,
11 May 2026
-
Ashly's death is an incomprehensible tragedy.—
Julia Bonavita,
FOXNews.com,
6 May 2026
Adjective
-
And with tight refurbishment and decommissioning timelines, along with fire safety and hazardous substance compliance risks, many organizations simply don’t have the time to experiment with circularity techniques and default to funneling recyclable textiles into waste management.—
Jennifer Bringle,
Footwear News,
19 May 2026
-
Landry’s substantial golden parachute is likely to draw scrutiny from lawmakers and higher education watchdogs as Florida Republicans continue to push universities to demonstrate tighter oversight of spending and administration costs.—
Garrett Shanley,
Miami Herald,
19 May 2026
Adjective
-
In his view, a perspective from an external lens adds dimensionality to problems that may have become impervious or desensitized within a department.—
Daniel Fusch,
USA Today,
18 May 2026
-
The drug, daraxonrasib, works by targeting KRAS, a protein inside the cancer cells that was previously considered to be impervious.—
Cara Lynn Shultz,
PEOPLE,
14 May 2026
Adjective
-
Thousands of fans have also been engaging with Nikki’s increasingly obsessive, unsettling texts, voice notes and special deliveries after encountering cryptic billboards across Los Angeles and New York, each featuring her obsessive messages alongside a phone number inviting them to reach out.—
Pamela McClintock,
HollywoodReporter,
15 May 2026
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The film, which stars Hannah Einbinder as a filmmaker tasked with revamping a tired summer camp horror franchise with its cryptic lead played by Gillian Anderson in tow, is set to make its way to theaters this August.—
Christian Zilko,
IndieWire,
14 May 2026
Adjective
-
In a video from Reuters, Charles appeared to laugh off Stewart's comment and said something unintelligible before turning to shake hands with Rolling Stones guitarist Ronnie Wood, who also got a chuckle out of the exchange.—
Mike Snider,
USA Today,
12 May 2026
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Still, even as the memes become borderline unintelligible, Kirkslop contains an air of transgression that imbues the otherwise inane edits and images with perverse political undercurrents.—
Brady Brickner-Wood,
New Yorker,
29 Apr. 2026
Adjective
-
The spongy material is mostly made of air, yet nearly impermeable to both air and liquid.—
Brandee Gruener,
Southern Living,
29 Apr. 2026
-
The outer layer hardened and became impermeable.—
Catherina Gioino,
Fortune,
11 Apr. 2026
Cite this Entry
“Impenetrable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/impenetrable. Accessed 21 May. 2026.
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