IMPENETRABLE Synonyms: 141 Similar and Opposite Words

impenetrable

adjective

(ˌ)im-ˈpe-nə-trə-bəl

Definition of impenetrable

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

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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Antonyms & Near Antonyms

as in incomprehensible

impossible to understand the textbook's language is completely impenetrable, at least to me

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Antonyms & Near Antonyms

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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Antonyms & Near Antonyms

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

Adjective

The world building is easier to understand and less dense than Crescent City, and the tone is also the most indicative of SJM’s writing on the whole; Throne of Glass started as a YA series, then becomes more adult over time.

— Anna Moeslein, Glamour, 24 Oct. 2026
The mollusks can form dense colonies that clog pipes, obstruct water flow and foul boat motors.

— Daniel Hunt, Sacbee.com, 23 Oct. 2026

Definition of dense

Adjective

All the power of the government — investigative, technological, legal — has been thrown at finding these mysterious, diabolically clever ballot baddies.

— Los Angeles Times, Los Angeles Times, 20 Oct. 2026
After all, what better place to reveal the mysterious professor’s identity than in the very magazine responsible for making the fictional detective an international sensation?

— Literary Hub, Literary Hub, 20 Oct. 2026

Definition of mysterious

Adjective

Days before the openings, the prospect of showing across his hometown still seemed to Hodges about as incomprehensible as a dream.

— Tara Anne Dalbow, Los Angeles Times, 21 Oct. 2026
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

Definition of incomprehensible

Adjective

Opinion polls predict tight race Domestically, Vucic has pledged higher pensions and public sector salaries, investment in state healthcare and subsidies for young couples.

— Reuters, NBC news, 25 Oct. 2026
Both parties expect whoever wins in November to do so by a tight margin in a state of 738,000 people.

— Arkansas Online, Arkansas Online, 24 Oct. 2026

Definition of tight

Adjective

Waititi and co-screenwriter Dahvi Waller seem impervious to that refined sensibility, instead preferring to slather on the quirks, to stunningly charmless effect.

— David Rooney, HollywoodReporter, 20 Oct. 2026
As coastal areas become more developed, impervious surfaces—like roadways, parking lots, rooftops, and sidewalks—have increased.

— Lydia Mansel, Travel + Leisure, 14 Oct. 2026

Definition of impervious

Adjective

Here’s a prime example of a more cryptic style of clue that sometimes pops up in late-week puzzles.

— Sean McGowan, New York Times, 22 Oct. 2026
Kermode was curious, if not slightly annoyed about all this cryptic communication and the request for a secret rendezvous.

— David Fear, Rolling Stone, 18 Oct. 2026

Definition of cryptic

Adjective

In fact, it is rooted in the same rhetoric as the black box metaphor, which similarly blurs the complex aspects of AI by framing inner workings as confined and unintelligible.

— Trent Wintermeier, The Conversation, 19 Oct. 2026
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

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

Style

“Impenetrable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/impenetrable. Accessed 28 Oct. 2026.

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Synonyms of impenetrable

adjective

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