im·​preg·​na·​ble | \ im-ˈpreg-nə-bəl How to pronounce impregnable (audio) \

Definition of impregnable

1 : incapable of being taken by assault : unconquerable an impregnable fortress
2 : unassailable also : impenetrable impregnable walls

Other Words from impregnable

impregnability \ (ˌ)im-​ˌpreg-​nə-​ˈbi-​lə-​tē How to pronounce impregnable (audio) \ noun
impregnableness \ im-​ˈpreg-​nə-​bəl-​nəs How to pronounce impregnable (audio) \ noun
impregnably \ im-​ˈpreg-​nə-​blē How to pronounce impregnable (audio) \ adverb

Did you know?

Impregnable is one of the many English words that bear a French ancestry, thanks to the Norman conquest of England in 1066. It derives from the Middle French verb prendre, which means "to take or capture." Combining prendre with various prefixes has given our language many other words, too, including surprise, reprise, and enterprise. Remarkably, impregnable has a different origin from the similar-looking word pregnant; that word comes from a different Latin word, praegnas, meaning "carrying a fetus."

Examples of impregnable in a Sentence

an impregnable fortress that had foiled one invader after another over the centuries the castle's supposedly impregnable walls
Recent Examples on the Web Ultimately Greenwood and Hanke imagine a United States that’s an autarkic, wholly impregnable island of finance and subsequent economic activity. John Tamny, Forbes, 17 Apr. 2022 That should strike a cautionary note in the executive suites of other companies that seem to hold impregnable positions at the summit of the business world, such as Alphabet (the parent of Google) and Amazon. Michael Hiltzik, Los Angeles Times, 4 Feb. 2022 To be sure, the economic wall around Russia is not impregnable. Washington Post, 18 Mar. 2022 The thick-walled bunker is just one impregnable symbol of resistance and survival, shown with pride in this frigid city, which has already withstood two weeks of Russian ground attacks and sporadic rocket fire. Scott Peterson, The Christian Science Monitor, 14 Mar. 2022 Powered by these two political-economic projects, the Democratic coalition loomed across mid-century American politics as a seemingly impregnable electoral Death Star. Sam Rosenfeld, The New Republic, 15 Feb. 2022 Taylor rushed for 170 yards and one touchdown against the seemingly impregnable New England Patriots defense in a 27-17 victory in Week 15, which moved the Colts toward the front of the A.F.C. wild-card chase. New York Times, 22 Dec. 2021 Fain takes some time to gloat in front of our guy Perrin before exiting stage right as if getting into the throne room of a previously impregnable city were the easiest thing in the world. Sean T. Collins, Vulture, 24 Dec. 2021 The conservative bloc of that era was not impregnable, however. Michael Hiltzik, Los Angeles Times, 17 Dec. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'impregnable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of impregnable

15th century, in the meaning defined at sense 1

History and Etymology for impregnable

Middle English imprenable, from Middle French, from in- + prenable vulnerable to capture, from prendre to take — more at prize

Learn More About impregnable

Time Traveler for impregnable

Time Traveler

The first known use of impregnable was in the 15th century

See more words from the same century

Listen to Our Podcast About impregnable

Dictionary Entries Near impregnable




See More Nearby Entries 

Statistics for impregnable

Last Updated

7 May 2022

Cite this Entry

“Impregnable.” Dictionary, Merriam-Webster, Accessed 2 Jul. 2022.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

More Definitions for impregnable


im·​preg·​na·​ble | \ im-ˈpreg-nə-bəl How to pronounce impregnable (audio) \

Kids Definition of impregnable

: not able to be captured by attack : unconquerable

More from Merriam-Webster on impregnable

Nglish: Translation of impregnable for Spanish Speakers

Britannica English: Translation of impregnable for Arabic Speakers


Test Your Vocabulary

Words Named After People

  • name tags
  • Namesake of the leotard, Jules Léotard had what profession?
Spell It

Can you spell these 10 commonly misspelled words?

Universal Daily Crossword

A daily challenge for crossword fanatics.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!