impenetrable /im-penˈi-trə-bl/

1. Incapable of being penetrated
2. Impervious
3. Inscrutable
4. Occupying space exclusively (physics)

• adversaria
• adversarial
• adversaries
• adversary
• adversative
• adverse
• adversely
• adverseness
• adversenesses
• adverser
• adversest
• adversities
• adversity
• advert
• adverted
• advertence
• advertences
• advertencies
• advertency
• advertent
• advertently
• adverting
• advertise
• advertised
• advertisement