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 Minutes earlier, the players paraded around Azteca Stadium — traditionally an impenetrable fortress — to applaud El Tri fans with tears in their eyes. — Eduard Cauich, Los Angeles Times, 12 July 2026 The package depicts the usual impenetrable forest of the GAS packaging in stark, thorny monochrome. — Daniel Bromfield, Pitchfork, 7 July 2026 In the venue’s defense, the arena’s near-impenetrable exterior likely had something to do with its appeal. — Alli Rosenbloom, CNN Money, 1 July 2026 In spite of D'Arcy's best efforts, Rhaenyra is an impenetrable character with illogical choices and zero magnetism to the viewers (or seemingly, her councilors). — Kelly Lawler, USA Today, 21 June 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
  • Out in the wild, turbulent air swirls these plumes into a chaotic, broken landscape—dense chemical filaments laced through long stretches of clean air.
    — Jacek Krywko, ArsTechnica, 1 Aug. 2026
  • This breakthrough could eventually lead to smaller, denser, and more efficient photonic chips for communications, quantum technologies, and optical computing.
    — Rupendra Brahambhatt, Interesting Engineering, 1 Aug. 2026
Definition of dense
Adjective
  • Then there’s the new, mysterious character played by Sadie Sink, introducing a major element of MCU lore that has very little to do with Spider-Man.
    — David Sims, The Atlantic, 30 July 2026
  • And after a few days of searching, law enforcement received a mysterious eyewitness tip.
    — Dateline NBC, NBC news, 30 July 2026
Definition of mysterious
Adjective
  • But given the profundity of her subject matter and the near-universal awe her art inspires, perhaps this sense of futility gestures at the incomprehensible, even transcendent aura around Petviashvili’s works.
    — The Editors of ARTnews, ARTnews.com, 28 July 2026
  • Here are three stars that appear neatly connected overhead, but in reality, one is separated by an incomprehensible distance.
    — Jamie Carter, Space.com, 24 July 2026
Definition of incomprehensible
Adjective
  • With patience and selectivity, a tight budget can still open up the universe.
    — Damian Peach, Space.com, 4 Aug. 2026
  • Small prey, with smaller bodies, can make abrupt, tight turns.
    — Rachel Sargent Mirus, Hartford Courant, 3 Aug. 2026
Definition of tight
Adjective
  • Properties with at least five acres of impervious surface will be subject to the rules.
    — Ian James, Los Angeles Times, 29 July 2026
  • Since her move, Hampton has established herself as England’s No 1 and one of the WSL’s most impervious goalkeepers.
    — Megan Feringa, New York Times, 28 July 2026
Definition of impervious
Adjective
  • Corsini and Massimo Vavassori’s script is needlessly cryptic at times, leaving the central figure too much of an abstraction.
    — Dennis Harvey, Variety, 30 July 2026
  • Ella Rubin stars as Annie Jacobson, a high schooler who stumbles into a mystery when her grandfather dies and leaves her an island in Canada—along with a cryptic letter.
    — Kenneal Patterson, Vanity Fair, 27 July 2026
Definition of cryptic
Adjective
  • Claypool’s voice, formerly a sharp and declarative figure in the mix, slinks down into silty waters, often unintelligible and almost always emotionally ambiguous.
    — Sasha Geffen, Pitchfork, 2 Aug. 2026
  • The world premiere on Sunday – in the presence of Illumination boss Chris Meledandri and director Pierre Coffin, who is also the origin of the minions’ unintelligible chatter – kicks off one of the biggest Annecy Film Festival’s yet.
    — Melanie Goodfellow, Deadline, 19 June 2026
Definition of unintelligible
Adjective
  • State officials estimated the costs at $4,100 per acre of paved or impermeable surface for those that decide to help fund local stormwater projects, and said the costs for other options could be considerably higher.
    — Ian James, Los Angeles Times, 29 July 2026
  • Spain needed until the 106th minute to slip a Ferran Torres shot past the impermeable goalkeeping of Argentina’s Emiliano Martínez, whose championship-game record 11 saves proved one too few.
    — Jerry Brewer, New York Times, 20 July 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 5 Aug. 2026.

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Nglish: Translation of impenetrable for Spanish Speakers

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