1. (a.) Proof against penetration or permeation by water; impervious to water; as, a waterproof garment; a waterproof roof.

2. (n.) A substance or preparation for rendering cloth, leather, etc., impervious to water.

3. (n.) 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.

4. (v. t.) To render impervious to water, as cloth, leather, etc.

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