IMPREGNABLE Synonyms: 83 Similar and Opposite Words

impregnable

adjective

im-ˈpreg-nə-bəl

Definition of impregnable

as in invincible

incapable of being defeated, overcome, or subdued an impregnable fortress that had foiled one invader after another over the centuries

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in impervious

impossible to get through or into the castle's supposedly impregnable walls

Synonyms & Similar Words

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 impregnable Alexander the Great conquered it in 332 BCE after building a causeway to what had been considered an impregnable island fortress. — Jane Arraf, NPR, 23 June 2026 On that occasion a team made up of players who had all been born in Haiti shocked an Italy team famed for its impregnable defense. — Laurent Dubois, The Conversation, 10 June 2026 The multiple attacks could be a major victory for the jihadis in a city seen as impregnable, despite attackers often targeting troops and villages on the outskirts of the city. — Haruna Umar, Los Angeles Times, 17 Mar. 2026 Already fairly impregnable, the Oscars for years has been protected in public view and behind the scenes by a series of federal, regional and local law enforcement groups and departments working in coordination under the auspices of the LAPD. — Dominic Patten, Deadline, 11 Mar. 2026 See All Example Sentences for impregnable

Recent Examples of Synonyms for impregnable

Adjective

Hearing Ryan talk about particularly the metaphor for AIDS and what AIDS meant to him, and that AIDS was quite literally a thing killing beautiful young people in the ‘80s; people who felt untouchable and invincible.

— Jackie Strause, HollywoodReporter, 10 Sep. 2026
Cameron keeps upping the ante, until one becomes convinced the T-1000 is well-nigh invincible.

— ArsTechnica, ArsTechnica, 28 Aug. 2026

Definition of invincible

Adjective

None of the eight simulations were impervious to the threats, and even when agents detected a risk, the detection didn’t translate into the agents trying to contain the threat.

— Jake Angelo, semafor.com, 15 Sep. 2026
Many Russians may not regard Putin’s regime as solicitous of the public good, which could explain the withdrawal of capital from the country, but the regime is also accepted as a given, a distant presence impervious to outside influence.

— MICHAEL KIMMAGE, Foreign Affairs, 14 Sep. 2026

Definition of impervious

Adjective

Google also doesn’t claim that SynthID is invulnerable—the original paper on the technology notes that the watermark is not intended to withstand adversarial attacks.

— ArsTechnica, ArsTechnica, 29 July 2026
For Ross, this gives the character a steadier presence than the standard invulnerable operative often found in genre fiction.

— Matt Emma, USA Today, 29 July 2026

Definition of invulnerable

Adjective

But the advent of NIL has turned the gap into an unconquerable chasm.

— Dana O’Neil, CNN Money, 6 Sep. 2026
The rescue party made its way to New York harbor by train, private car, and then two bicycles shared among the three of them—Frank, Sarah’s husband, on one; Sarah and Billo on the other—when shipyard traffic proved unconquerable by automobile.

— Claire Carusillo, Harpers Magazine, 4 Aug. 2026

Definition of unconquerable

Adjective

Morton kosher salt is also very common in home kitchens, but has denser grains than Diamond Crystal.

— Chris Morocco, Bon Appetit Magazine, 26 Sep. 2026
This approach could eventually help make magnetic memory faster, denser, and more energy efficient.

— Rupendra Brahambhatt, Interesting Engineering, 26 Sep. 2026

Definition of dense

Adjective

Austria made the Final 8 after Jurji Rodionov beat Belgium’s Zizou Bergs 7-6, 6-3 to build an insurmountable 3-1 advantage.

— ABC News, ABC News, 19 Sep. 2026
The report highlights that even as fiber lines are extended into rural areas and billions of federal and state dollars are deployed, affordability and access remain insurmountable barriers for many families.

— Erin Mote, Forbes.com, 15 Sep. 2026

Definition of insurmountable

Adjective

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
Director Padraic McKinley’s debut feature stars Ethan Hawke as a battle-scarred veteran hired to smuggle a fortune in gold across 100 miles of impenetrable wilderness.

— Payton Turkeltaub, Variety, 19 Sep. 2026

Definition of impenetrable

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“Impregnable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/impregnable. Accessed 2 Oct. 2026.

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Synonyms of impregnable

adjective

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