1. the quality or state of being impossible to pass through or traverse

Examples

• The impassableness of the mountain range made it a natural border between the two regions.
• Heavy snow increased the impassableness of the rural roads during winter.
• The river's impassableness prevented travelers from crossing to the other side.
• Engineers had to address the impassableness of the flooded highway.
• The dense jungle's impassableness made exploration extremely difficult.