Made of or coated or treated with rubber, plastic, or a sealing agent to prevent penetration by water, Proof against penetration or permeation by water; impervious to water, Made of or covered with material that doesn't allow water in, verb_ To make waterproof or water-resistant, make watertight, transitive verb_ To make impervious to water, To render impervious to water, as cloth, leather, etc, noun_ a water-resistant coat, 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, Any material which repels water; especially, a light woolen cloth made for the purpose, and subjected to some waterproofing application