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 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 The Shiatsung Project In a bungalow surrounded by an impenetrable wall, a woman has been raised in isolation by a talking screen mounted on the living room wall, fullfilling her every wish without ever revealing the reasons for its life and existence. — Kevin Giraud, Variety, 18 June 2026 For 82 games and three-plus playoff rounds, the bunker remained impenetrable. — Kristian Winfield, New York Daily News, 9 June 2026 Which is okay, because the XLE serves as something of an impenetrable panic room and command center once parked. — New Atlas, 9 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
  • If caught in dense blowing dust, pull off the road, turn off your lights and keep your foot off the brake.
    — CA Weather Bot, Sacbee.com, 10 July 2026
  • The 23 crew members fought through dense fog and dealt with equipment issues after leaving port on June 5.
    — Jennifer Ouellette, ArsTechnica, 10 July 2026
Definition of dense
Adjective
  • In Season 1, the mysterious deep-space research vessel USCSS Maginot, which crash-lands on Earth.
    — Rosy Cordero, Deadline, 9 July 2026
  • And Miles starts to notice a mysterious woman in not just one of his photos.
    — Georg Szalai, HollywoodReporter, 9 July 2026
Definition of mysterious
Adjective
  • There have been times when acts of atrocity have been going on — and gosh, some of those things are incomprehensible — yet humanity has found a way.
    — Ryan Gajewski, HollywoodReporter, 27 June 2026
  • Being joyful there — in the Dominican Republic, where small shacks and houses pieced together by junkyard scraps sometimes hold families with over a dozen members — seems incomprehensible.
    — Daniel Flick, AJC.com, 25 June 2026
Definition of incomprehensible
Adjective
  • Despite persistent inflation and tighter household budgets, Bankrate analyst Alex Gailey says even small financial adjustments can make a meaningful difference over time.
    — Bonnie Laden, CBS News, 14 July 2026
  • Pilots are launching into a bottleneck already packed with ferries, commercial vessels, and tour boats, while sharing tight overhead airspace with NYPD, news, and helicopters, often with limited visibility.
    — Janet Handal, New York Daily News, 13 July 2026
Definition of tight
Adjective
  • The problem is… their opponents will likely be France, a team that looks impervious.
    — Carl Anka, New York Times, 4 July 2026
  • Overloading Your Washer Even the softest of towels are not impervious to improper laundering, and overloading your washer or using too little water can affect how thoroughly the towels are washed.
    — Louise Parks, Martha Stewart, 30 June 2026
Definition of impervious
Adjective
  • It was filled with brackets and parentheticals, written in different fonts and colors, much of it in capital letters, at once detailed and cryptic.
    — Joaquin Sapien, ProPublica, 30 June 2026
  • His doctors speculated his infection might have been a rare case of cryptic transmission from sharing meals and bathrooms with his coworkers, one of whom apparently had a tapeworm infection.
    — Beth Mole, ArsTechnica, 26 June 2026
Definition of cryptic
Adjective
  • 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
  • The adversaries made for a striking scene, exchanging insults in mutually unintelligible languages in the dead of night.
    — Literary Hub, Literary Hub, 16 June 2026
Definition of unintelligible
Adjective
  • Chocolate brown stripes punctuate a light charcoal gray background, and the low-pile weave made from recycled polyester gives it an impermeable, easy-to-clean surface.
    — Julia Harrison, Architectural Digest, 26 June 2026
  • Needing to remain impermeable to everything that is said about him is another stylistic exercise built into the equation of being a global star.
    — TIME, Time, 26 June 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 17 Jul. 2026.

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More from Merriam-Webster on impenetrable

Nglish: Translation of impenetrable for Spanish Speakers

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