Definition of impregnable in English:



  • 1(of a fortified position) unable to be captured or broken into.

    ‘a massive and impregnable fortress’
    figurative ‘the seat I was offered appeared to be an impregnable Tory stronghold’
    • ‘But he had other things in mind - plans that had been consuming his soul since he had escaped from La Fortaleza, the once impregnable fortress that had fallen a little over a year ago.’
    • ‘Incredibly sturdy, it had been built to serve as a nuclear bomb shelter if necessary, supposedly an impregnable fortress of civil defense.’
    • ‘In their accounts of hunting for a way out, they provide a survey of a border territory, an impregnable zone through which the people imprisoned above would never pass.’
    • ‘The key to the Belgian defence along the Albert Canal was the supposedly impregnable fortress of Eben-Emael.’
    • ‘Yes sir, but we think that the position is impregnable and we can hold it against far superior forces.’
    • ‘In the middle of Hue, however, was a virtually impregnable fortress known as the Citadel, with towers, ramparts, moats, concrete walls, and bunkers.’
    • ‘However, instead of building the fort on a hill, the impassable wetlands were used to create an impregnable site, the biggest marshland in England.’
    • ‘No doubt it will go the way of all seemingly impregnable empires of the past.’
    • ‘I'm satisfied this place is nearly impregnable.’
    • ‘On 15 September French and Serbian mountain troops successfully attacked hitherto impregnable Bulgarian positions.’
    • ‘The castle had been built with a good eye for defense; this place was virtually impregnable.’
    • ‘Later, he began building model castles, surrounded by fortified emplacements, and he spent hours studying the virtually impregnable fortifications of Vauban.’
    • ‘In the face of these pressures, Anglican natural theology retreated into the apparently impregnable fortress of biology.’
    • ‘But sometime during the final week your impregnable fortress crashes and burns, but you land on your feet at the very end of the month.’
    • ‘Labyrinthine streets of ancient slum housing traversed the steep hill up to the impregnable city walls.’
    • ‘There has to be something; no fortress is completely impregnable.’
    • ‘The walls surrounding the city were impregnable, never before breached by an attacking army.’
    • ‘Austria ruled directly only in the newly formed Kingdom of Lombardy-Venetia, but from the impregnable fortresses of the Quadrilateral in the central Po Valley Austrian bayonets could reach any part of Italy.’
    • ‘Singapore, an island at the southern end of the Malay Peninsula, was considered a vital part of the British Empire and supposedly impregnable as a fortress.’
    • ‘Between them they created a seemingly impregnable fortress, naturally protected on three sides by cliffs and defended by concentric lines of mutually supporting fortifications.’
    invulnerable, impenetrable, unattackable, unassailable, inviolable, secure, strong, stout, safe, well fortified, well defended
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    1. 1.1 Unable to be defeated or overcome.
      ‘Liverpool used their good fortune to forge an impregnable lead’
      • ‘He required forceful persuasion to forego county commitments to fly back for the final, but no-one smiled brighter after the previously impregnable Ireland had been clinically defeated by 47 runs.’
      • ‘The victory stretched their 100 percent winning sequence to 19 matches and they now have an impregnable nine point lead at the top.’
      • ‘He was impregnable, unbeatable, and nothing, no creature could even come close to conquering the mighty Kong.’
      • ‘Still, to perfect one's play at Worms, you will have to spend a lot of time learning the nuances of each weapon and tricks on how to defeat what seems like an impregnable AI.’
      • ‘Then, without warning, you've got the world's number one goalkeeper in self-destruct mode, the England captain glancing an own goal home and a seemingly impregnable lead overturned.’
      • ‘But Preston were knocked sideways by the shock of seeing their impregnable lead suddenly wiped out.’
      • ‘After all, within the space of a three-month election campaign she managed to squander a seemingly impregnable lead of 22 percent over the SPD.’
      • ‘He's seen what looked like an impregnable 22-point lead slashed to just two ahead of me.’
      unassailable, unbeatable, undefeatable, unshakeable, invincible, indomitable, unconquerable, unstoppable, invulnerable
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Late Middle English: from Old French imprenable, from in- ‘not’ + prendre ‘take’ (from Latin prehendere). The current spelling arose in the 16th century, perhaps influenced by Old French variants.