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

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Antonyms & Near Antonyms

as in impervious

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

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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 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

Cameron keeps upping the ante, until one becomes convinced the T-1000 is well-nigh invincible.

— ArsTechnica, ArsTechnica, 28 Aug. 2026
Panettiere featured as the virtually invincible high school cheerleader Claire Bennet on the series across four seasons.

— Charisma Madarang, Rolling Stone, 19 Aug. 2026

Definition of invincible

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

California Cruise is even closer than expected, with deliveries slated to begin next year.

— New Atlas, New Atlas, 30 Aug. 2026
The success of this trial was possible through the close and constructive cooperation between the participating German Air Force organisations, the exercise management team and the expert teams from Rheinmetall Air Defence and Hensoldt.

— Prabhat Ranjan Mishra, Interesting Engineering, 30 Aug. 2026

Definition of close

Adjective

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
The Spurs led for more minutes than the Knicks and built seemingly unconquerable leads.

— Dana O’Neil, CNN Money, 14 June 2026

Definition of unconquerable

Adjective

Autumn Joy Stonecrop Also called autumn joy sedum, this hardy, summer- and fall-flowering perennial is known for its succulent foliage and dense clusters of tiny pink flowers.

— Alexandra Jones, The Spruce, 30 Aug. 2026
There was less consensus about the dust kicked up from the playa, which can be dense enough to cause whiteouts.

— Henry Alford, New Yorker, 29 Aug. 2026

Definition of dense

Adjective

Child safety experts lauded the settlement and the accompanying pressure campaign as a giant leap forward in the effort to regulate an industry that until this year appeared all but impenetrable to reform, either from the courts or legislatures.

— Sonja Sharp, Los Angeles Times, 29 Aug. 2026
The space offers guests a rare glimpse into a facet of Japanese nightlife that can feel impenetrable to outsiders.

— Condé Nast, Condé Nast Traveler, 26 Aug. 2026

Definition of impenetrable

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“Impregnable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/impregnable. Accessed 1 Sep. 2026.

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Synonyms of impregnable

adjective

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