impenetrable

adjective

(ˌ)im-ˈpe-nə-trə-bəl How to pronounce impenetrable (audio)
Definition of impenetrablenext
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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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

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 impenetrable The San Juans are among the most impenetrable mountains in the West. — Peter Hessler, New Yorker, 28 Sep. 2026 Yet the very top echelon remains for the most part impenetrable. — Emma Hinchliffe, Fortune, 28 Sep. 2026 Though Best Original Song can seem impenetrable, as the Music Branch that determines the shortlist and nominees for the category has its own insular politics, Swift has inched her way closer to a nomination with every song she’s written for a film. — Marcus Jones, IndieWire, 26 Sep. 2026 But even with the Bills having the near-consensus best quarterback in football, this Buffalo team isn't impenetrable, and the Lions have plenty of big-time road experience that could lead to an early-season upset. — Christian Romo, Freep.com, 17 Sep. 2026 See All Example Sentences for impenetrable
Recent Examples of Synonyms for impenetrable
  1. dense
  2. mysterious
  3. incomprehensible
  4. tight
  5. impervious
  6. cryptic
  7. unintelligible
  8. impermeable
Adjective
  • This is a dense picture—there’s almost too much to unpack, if you can be bothered to care about any of it.
    — Stephanie Zacharek, Time, 16 Oct. 2026
  • Supplemental screening will move into the mainstream for women with dense breasts.
    — Samantha Agate, Miami Herald, 16 Oct. 2026
Definition of dense
Adjective
  • Someone who has regarded filmmaking as a mysterious occupation might begin to see a way into it.
    — Philip Martin, Arkansas Online, 13 Oct. 2026
  • But despite these regular airings, the origin of the mysterious Jardine Star Brooch has remained tantalizingly unexplained for decades.
    — Eva Wolchover, Vanity Fair, 13 Oct. 2026
Definition of mysterious
Adjective
  • Stanton’s confession ends up being incomprehensible to anyone but himself—an irony that McCarthy, with his partiality for secret codes, seems to take great pleasure in.
    — Max Callimanopulos, New Yorker, 14 Oct. 2026
  • Sure, the story is incomprehensible, and Dylan is far from a great actor.
    — Andy Greene, Rolling Stone, 3 Oct. 2026
Definition of incomprehensible
Adjective
  • Certain oils can soften dry, flaky skin and help reduce moisture loss, which may be especially helpful if your scalp feels tight or dry after shampooing.
    — Lauren Jarvis-Gibson, Miami Herald, 17 Oct. 2026
  • Republicans are fighting to hold on to the Texas Senate seat, as polls point to a tight race between Paxton and Democratic opponent James Talarico.
    — Joe Walsh, CBS News, 16 Oct. 2026
Definition of tight
Adjective
  • Over the summer, the Commanders’ coach, Dan Quinn, dreaming up ways to make his staff more impervious to pressure, enlisted the help of the intelligence establishment of the United States.
    — Vinson Cunningham, New Yorker, 9 Oct. 2026
  • Josh Allen is elite, but the Bills aren’t impervious to problems — check out the Chargers game.
    — Los Angeles Times, Los Angeles Times, 8 Oct. 2026
Definition of impervious
Adjective
  • The cryptic eco-disaster project will represent a loss of hundreds of millions when all is said and done.
    — Matt Donnelly, Variety, 9 Oct. 2026
  • Emanuel’s cryptic comment comes amid claims that Meghan was in early talks to star in the third season of Guy Ritchie’s Netflix series The Gentlemen.
    — Allison DeGrushe, StyleCaster, 30 Sep. 2026
Definition of cryptic
Adjective
  • Painter expressed concern that paper trail may one day become unintelligible if AI models begin using their own language to track their steps.
    — Lisa Eadicicco, CNN Money, 16 Oct. 2026
  • While the audio recordings are mostly unintelligible to human ears, Energize Lab isn’t supposed to be storing any audio at all.
    — Sean Hollister, The Verge, 15 Oct. 2026
Definition of unintelligible
Adjective
  • Charlotte has been blessed to grow at a fast rate, but our expansion has removed green spaces with impermeable pavement and buildings.
    — Charlotte Observer, Charlotte Observer, 6 Oct. 2026
  • Sign up for the newsletter When the rain does fall, Kabul’s hard, impermeable surfaces mean the water doesn’t replenish aquifers, but instead sweeps through the city as flash floods, destroying homes, killing people and rolling away.
    — Laura Paddison, CNN Money, 6 Oct. 2026
Definition of impermeable

Browse Nearby Words

impenetrability
impenetrable
impenitence
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Cite this Entry

“Impenetrable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/impenetrable. Accessed 21 Oct. 2026.

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