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 rule also failed to tackle all of the ways trusts and other vehicles provide impenetrable secrecy for the wealthy and the crooked alike. — Casey Michel, The Atlantic, 14 Aug. 2026 As intimidating as these mountains may appear, a simple drive can actually take you deep into this seemingly impenetrable wilderness. — Cu Fleshman, Travel + Leisure, 13 Aug. 2026 Cody erects impenetrable emotional walls around him that deny him from asking for help and creating community. — Randy Myers, Mercury News, 12 Aug. 2026 There was a metal gate rolled out making the front portion of the plane an impenetrable fortress. — David Hookstead Outkick, FOXNews.com, 7 Aug. 2026 See All Example Sentences for impenetrable

Recent Examples of Synonyms for impenetrable

Adjective

Fires routinely sweep Kinshasa’s dense neighborhoods during the dry season, where rapid urban growth outpaces basic protections such as reliable fire and emergency services.

— Saleh Mwanamilongo, Los Angeles Times, 5 Sep. 2026
There comes a moment, looking at Evans’s dense worlds, when the eye stops decoding and the mind begins to surrender.

— Doreen St. Félix, New Yorker, 5 Sep. 2026

Definition of dense

Adjective

In crucial moments the music fleetingly becomes mysterious, even ominous, with minor-key harmonies and a twisting vocal turn doubled by the bass line of the piano part.

— Literary Hub, Literary Hub, 10 Sep. 2026
These three mysterious elements of the cosmos have played a vital role in the evolution of large-scale cosmic structures like galaxies and galaxy clusters.

— Robert Lea, Space.com, 10 Sep. 2026

Definition of mysterious

Adjective

Of all the awful plays the Carolina defense made Sunday in a 59-37 loss to the Chicago Bears, two of the most incomprehensible came from one of their best and smartest players.

— Scott Fowler, Charlotte Observer, 13 Sep. 2026
The first two interceptions weren’t great, but the third one was truly incomprehensible.

— Chad Graff, New York Times, 11 Sep. 2026

Definition of incomprehensible

Adjective

Kevin Jairaj / Imagn Images During an early August practice, Hurts was unusually expressive after completing a deep pass down the middle to Elijah Moore in tight coverage.

— Brooks Kubena, New York Times, 8 Sep. 2026
Room for Disagreement Some Democrats were worried less about their individual candidates or the DCCC’s ability to compete, and more about the Democratic National Committee’s ability to help candidates in tight raises.

— Nicholas Wu, semafor.com, 8 Sep. 2026

Definition of tight

Adjective

Though the Gallaghers weren’t on hand at the film’s press conference earlier on Saturday to field questions, the band has posted several cryptic teasers on Instagram that have sent fans into detective mode.

— Ellise Shafer, Variety, 5 Sep. 2026
Sasha Farber posted a cryptic photo following his absence from DWTS’ season 35 lineup.

— Leigh Blickley, Entertainment Weekly, 4 Sep. 2026

Definition of cryptic

Adjective

Assuming viewers understood the history of English soccer — or even the offside rule — could make the broadcasts unintelligible for new fans who understood neither.

— Los Angeles Times, Los Angeles Times, 1 Sep. 2026
Incomplete, corrupted, untimely, or unintelligible Submissions or Submission Forms will be disqualified.

— August 16, NPR, 16 Aug. 2026

Definition of unintelligible

Adjective

Playing the American League’s best team, the Padres had the final two games of the series in hand before the practically impermeable back end of their bullpen blew late leads.

— Kevin Acee, San Diego Union-Tribune, 31 Aug. 2026
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

Definition of impermeable

Browse Nearby Words

impenetrability

impenetrable

impenitence

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Cite this Entry

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“Impenetrable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/impenetrable. Accessed 15 Sep. 2026.

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Synonyms of impenetrable

adjective

Example Sentences

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