Impregnable (?), a. [F. imprenable; pref. im- not + prenable pregnable, fr. prendre to take, L. prehendere. See Comprehend, Get to obtain.] Not to be stormed, or taken by assault; incapable of being subdued; able to resist attack; unconquerable; as, an impregnable fortress; impregnable virtue.
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The man's affection remains wholly unconcerned and impregnable. South.

-- Im*preg"na*ble*ness, n. -- Im*preg"na*bly, adv.
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