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 Instead, my trembling body was confronted by an impenetrable wall of rock. — Literary Hub, 6 Aug. 2026 The stormy painting conjures the first moments of In the Hand of Dante, as the titular character, portrayed by Oscar Isaac, scales perilously steep steps to what seems an impenetrable stronghold. — A.d. Amorosi, SPIN, 6 Aug. 2026 At a time when Disney’s once-impenetrable Marvel Cinematic Universe has been exhibiting concerning signs of wear and tear at the box office, Spider-Man is getting more and more powerful. — Rebecca Rubin, Variety, 28 July 2026 The Phalanx was composed of men who moved and fought as one cohesive unit, creating an impenetrable wall of interlocking shields. — Steve Muscato, Forbes.com, 27 July 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
  • Elevated on an all-wood frame and ringed by tall evergreens, the home feels like a slice of Lake Tahoe in the middle of a dense suburb.
    — David Caraccio, Sacbee.com, 15 Aug. 2026
  • They are being sculpted by intense radiation from nearby young stars, while new stars are forming inside the dense clouds.
    — Kaif Shaikh, Interesting Engineering, 15 Aug. 2026
Definition of dense
Adjective
  • Although the bars are not related, all three arrived on the scene under purposefully mysterious circumstances.
    — Henri Hollis, AJC.com, 20 Aug. 2026
  • Dodson update One of the mysterious developments Thursday was linebacker Dodson leaving the field after individual drills.
    — Barry Jackson, Miami Herald, 20 Aug. 2026
Definition of mysterious
Adjective
  • Farnaby’s character, a thickly-accented and mostly-incomprehensible farmer, was, of course, called Barry.
    — Alex Ritman, Variety, 7 Aug. 2026
  • The scale of the commercial-military symbiosis between Washington and Silicon Valley is almost incomprehensible.
    — Alex Capri, Fortune, 4 Aug. 2026
Definition of incomprehensible
Adjective
  • Luchanko often creates chances for his teammates on the move, in tight and off the edge.
    — Corey Pronman, New York Times, 18 Aug. 2026
  • If money is tight, families tend to prioritize keeping boys in school, even if girls show more promise, experts say.
    — ABC News, ABC News, 18 Aug. 2026
Definition of tight
Adjective
  • This brand makes impervious base layers with a chemical-free blend of nylon and lycra.
    — Olivia Young, Travel + Leisure, 13 Aug. 2026
  • To deal with the settling, Peters and his team developed flexible flooring lined with an impervious three-ply fabric.
    — Jennifer Tucker, The Conversation, 7 Aug. 2026
Definition of impervious
Adjective
  • In response to a cryptic message, Hal rockets to Rushville—literally, because his ring gives him the power of flight—arriving to a murder scene and leaving a confused John to follow by plane.
    — Judy Berman, Time, 14 Aug. 2026
  • The messaging was somewhat cryptic, but that was his way of saying goodbye.
    — Jason Anderson, Sacbee.com, 12 Aug. 2026
Definition of cryptic
Adjective
  • Incomplete, corrupted, untimely, or unintelligible Submissions or Submission Forms will be disqualified.
    — August 16, NPR, 16 Aug. 2026
  • When the surveillance footage resumes about an hour later, a man can be heard shouting, but the words are unintelligible, and a vehicle horn sounds.
    — Kansas City Star, Kansas City Star, 10 Aug. 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 22 Aug. 2026.

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More from Merriam-Webster on impenetrable

Nglish: Translation of impenetrable for Spanish Speakers

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