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Showing results for waterproof. Search instead for waterproofed.
Synonyms

waterproof

American  
[waw-ter-proof, wot-er-] / ˈwɔ tərˌpruf, ˈwɒt ər- /

adjective

  1. impervious to water.

  2. rendered impervious to water by some special process, as coating or treating with rubber.

    a waterproof hat.

noun

  1. Chiefly British. a raincoat or other outer coat impervious to water.

  2. any of several coated or rubberized fabrics that are impervious to water.

verb (used with object)

  1. to make waterproof.

waterproof British  
/ ˈwɔːtəˌpruːf /

adjective

  1. not penetrable by water Compare water-repellent water-resistant

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. a waterproof garment, esp a raincoat

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. to make (a fabric, item of clothing, etc) waterproof

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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

  • waterproofer noun
  • waterproofness noun

Etymology

Origin of waterproof

First recorded in 1730–40; water + -proof

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.

Rubber was popular in the early 19th century because it was waterproof and flexible.

From The Wall Street Journal • Apr. 4, 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

It is "probably the most dangerous time for adult Emperor penguins because they haven't got their waterproof suits on," he says.

From BBC • Feb. 25, 2026

“Wrap your certificates in waterproof bags and make sure those are the first things you take if we have to evacuate. Wrap your certificates in waterproof bags...”

From "Half of a Yellow Sun" by Chimamanda Ngozi Adichie

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.