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Synonyms

impregnable

1 American  
[im-preg-nuh-buhl] / ɪmˈprɛg nə bəl /

adjective

  1. strong enough to resist or withstand attack; not to be taken by force, unconquerable.

    an impregnable fort.

    Synonyms:
    invulnerable
    Antonyms:
    vulnerable
  2. not to be overcome or overthrown.

    an impregnable argument.

    Synonyms:
    unassailable

impregnable 2 American  
[im-preg-nuh-buhl] / ɪmˈprɛg nə bəl /

adjective

  1. susceptible to impregnation, as an egg.


impregnable 1 British  
/ ɪmˈprɛɡnəbəl /

adjective

  1. unable to be broken into or taken by force

    an impregnable castle

  2. unable to be shaken or overcome

    impregnable self-confidence

  3. incapable of being refuted

    an impregnable argument

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

impregnable 2 British  
/ ˌɪmprɛɡˈneɪtəbəl, ɪmˈprɛɡnəbəl /

adjective

  1. able to be impregnated; fertile

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Related Words

See invincible.

Other Word Forms

  • impregnability noun
  • impregnableness noun
  • impregnably adverb

Etymology

Origin of impregnable1

First recorded in 1400–50; late Middle English impregnable, imprenable, from Middle French, equivalent to im- im- 2 + prenable pregnable

Origin of impregnable2

impregn(ate) + -able

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In theory that threatens Apple’s impregnable walled garden.

From The Wall Street Journal

In 2015, the seemingly impregnable Central Belt – and beyond – in Scotland fell to the Scottish National Party from Labour.

From BBC

“Some criminals have understood that museums are not impregnable cultural fortresses,” said Pierre Noual, a French lawyer specializing in cultural heritage law.

From The Wall Street Journal

Singapore was considered impregnable, but it wasn’t prepared for an attack from the mainland, and its 60,000-strong garrison surrendered on Feb. 8, 1942, the worst defeat in British history.

From The Wall Street Journal

High-flying Crystal Palace are the only side to rival City's attacking threat, while Newcastle are living up to their name by being almost as impregnable at the back as Arsenal.

From BBC