impregnable /im-pregˈnə-bl/

1. That cannot be captured, broken into or taken by force
2. Which cannot be overcome, unassailable

• decussate
• decussated
• decussately
• decussates
• decussating
• decussation
• decussations
• DEd.
• dedal
• Dedalian
• dedans
• dedicant
• dedicants
• dedicate
• dedicated
• dedicatee
• dedicatees
• dedicates
• dedicating
• dedication
• dedicational
• dedications
• dedicative
• dedicator
• dedicatorial