Definition of "waterproof" []

• Impervious to or unaffected by water. (adjective)
• Made of or coated or treated with rubber, plastic, or a sealing agent to prevent penetration by water. (adjective)
• A material or fabric that is impervious to water. (noun)
• Chiefly British A raincoat or other such outer garment. (noun)
• To make impervious to water. (verb-transitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Water perification of some sort. knife matches in waterproof container. compass"
• "Â This was also in waterproof ink, but using a finer point pen."
• "The jacket no longer has a main waterproof zipper."