What does "impregnable" mean?

Impregnable: Not to be stormed, or taken by assault; incapable of being subdued; able to resist attack; unconquerable; as, an impregnable fortress; impregnable virtue. The man's affection remains wholly unconcerned and impregnable. South. -- Im*preg"na*ble*ness, n. -- Im*preg"na*bly, adv.

Additional senses

  1. 2.Capable of being impregnated, as the egg of an animal, or the ovule of a plant.

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