When something is impregnable it is not easily taken by force and can stand up to any attack. We usually use it in reference to some form of protection, like a fort or a solid defensive line in football.

The genealogy of the adjective impregnable includes the Middle French word prenable, meaning "vulnerable, easily conquered," which itself came from the verb prendre, which meant "to take." The addition of the negative prefix im- flipped the meaning. Impregnable can be used to describe anything that cannot be entered or successfully attacked. Seventeenth-century theater critic Jeremy Collier once said, "True courage is a result of reasoning. A brave mind is always impregnable."

Definitions of impregnable
  1. adjective
    immune to attack; incapable of being tampered with
    “an impregnable fortress”
    synonyms: inviolable, secure, strong, unassailable, unattackable
    immune to attack; impregnable
  2. adjective
    incapable of being overcome, challenged, or refuted
    “an impregnable argument”
    impregnable self-confidence”
    synonyms: inexpugnable
    not capable of being conquered or vanquished or overcome
  3. adjective
    capable of conceiving
    synonyms: conceptive
    capable of reproducing
Word Family

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