Webster's Revised Unabridged Dictionary · 1913

Waterproof

Waterproof , adjective

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

Waterproof , noun

1.
A substance or preparation for rendering cloth, leather, etc., impervious to water.
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.

Waterproof , transitive verb

To render impervious to water, as cloth, leather, etc.