waterproof
Americanadjective
noun
verb (used with object)
adjective
noun
verb
Usage
What does waterproof mean? If something is waterproof, water can’t soak it or get inside of it. For example, waterproof boots will keep your feet dry even if you walk in water. Waterproof is also commonly used as a verb meaning to make something waterproof, as in We need to waterproof this basement so it won’t flood during rainstorms. Waterproof is sometimes used in the U. K. as a noun to refer to a waterproof garment, especially a raincoat, as in It’s raining, so you’d better wear your waterproof. Example: Make sure you get a waterproof tent—the ones that are only water-resistant can still let the rain in.
Other Word Forms
Etymology
Origin of waterproof
Explanation
Water can't penetrate something that's waterproof. Umbrellas and rain boots don't work very well if they're not waterproof. Waterproof jackets will keep you dry even if it starts to rain, and waterproof mascara won't run in black streaks down your face even if you're weeping at a sad movie. You can use this word as a verb, too: "We should waterproof the tent before we go camping this weekend — it's supposed to pour!" If you're British, you might also use waterproof as a noun, to mean a waterproof rain coat.
Vocabulary lists containing waterproof
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Each animal was equipped with a waterproof heart rate monitor, dive recorder, and radio transmitter.
From Science Daily • May 9, 2026
The mattress should be firm, flat and waterproof.
From BBC • May 5, 2026
Elon Musk tweeted in 2022 that the Cybertruck “will be waterproof enough to serve briefly as a boat.”
From Los Angeles Times • Mar. 19, 2026
And much like his newly purchased pad, Simmons’ former home “utilizes solar-power for pool and radiant heated flooring, eco-materials and fire-resistant, waterproof triple-panel windows.”
From MarketWatch • Feb. 27, 2026
In exchange the sergeant-major covers us over with a waterproof sheet.
From "All Quiet on the Western Front: A Novel" by Erich Maria Remarque
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
