What does "waterproof" mean?

Waterproof: A substance or preparation for rendering cloth, leather, etc., impervious to water.

Additional senses

  1. 2.Cloth made waterproof, or any article made of such cloth, or of other waterproof material, as rubber; esp., an outer garment made of such material.
  2. 3.To render impervious to water, as cloth, leather, etc.

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