( a. )
Not to be stormed, or taken by assault; incapable of being subdued; able to resist attack; unconquerable; as, an impregnable fortress; impregnable virtue.
( a. )
Not to be stormed, or taken by assault; incapable of being subdued; able to resist attack; unconquerable; as, an impregnable fortress; impregnable virtue.
Webster's Revised Unabridged English Dictionary. Пересмотренный полный словарь английского языка Webster. 2012