1. the quality or state of being impermeable; the inability of a substance to allow liquids or gases to pass through it

Examples

• The impermeability of the rubber coating makes it ideal for waterproofing.
• Scientists tested the impermeability of the new plastic membrane.
• The impermeability of the clay soil prevented water from draining properly.
• Engineers valued the impermeability of the material for use in protective barriers.
• The impermeability of the sealed container kept the contents fresh for months.