reverse osmosis


Definition of reverse osmosis

: the movement of fresh water through a semipermeable membrane when pressure is applied to a solution (such as seawater) on one side of it

Examples of reverse osmosis in a Sentence

Recent Examples on the Web The Golden State is a role model for the rest of the nation in the deployment of water recycling systems using reverse osmosis, drip irrigation and the seasonal rotation of crops to improve the soil. Peter Fimrite,, "California farms, ranches strive to adapt as climate warms — it’s a matter of survival," 19 Sep. 2019 Ranging from $200 to $1,800, a reverse osmosis system is typically the most expensive option and may require a professional plumber to install it under the sink. Los Angeles Times, "Here’s what you can (and can’t) do about PFAS contamination in your water," 23 Oct. 2019 Almost all new facilities planned in the region will use reverse osmosis, a trend likely to continue as budget-minded Gulf governments cut subsidies on fossil fuels. Washington Post, "Why Making Seawater Drinkable Doesn’t Thrill Everyone," 8 Mar. 2019 Cleaner, more energy-efficient technologies such as reverse osmosis -- passing seawater through plastic membranes to remove salt and other impurities -- have become more prevalent. Washington Post, "Why Making Seawater Drinkable Doesn’t Thrill Everyone," 8 Mar. 2019 Another under-sink filter with five stages, including reverse osmosis. Paige Szmodis, Popular Mechanics, "The 8 Best Water Filters to Purify Your Home’s Water," 28 June 2019 However, Walsh said the city is considering arranging to have reverse osmosis facilities on hand for emergencies. Molly Harbarger,, "Salem continues to tell vulnerable residents to avoid tap water: What should I know?," 31 May 2018 The process involves disinfecting the water with chlorine, then membrane filtration, reverse osmosis and ultra violet/advanced oxidation sterilization. Karen Pearlman, San Diego Union-Tribune, "Helix pledges additional $2.5 million for Padre Dam reclaimed water plan," 9 July 2019 Today, most water desalination uses reverse osmosis, which employs energy to push water through a membrane that excludes salts. Robert F. Service, Science | AAAS, "This former playwright aims to turn solar and wind power into gasoline," 3 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'reverse osmosis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of reverse osmosis

1921, in the meaning defined above

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Time Traveler for reverse osmosis

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The first known use of reverse osmosis was in 1921

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Statistics for reverse osmosis

Last Updated

9 Dec 2019

Cite this Entry

“Reverse osmosis.” The Dictionary, Merriam-Webster Inc., Accessed 11 December 2019.

More from Merriam-Webster on reverse osmosis

Rhyming Dictionary: Words that rhyme with reverse osmosis Encyclopedia article about reverse osmosis

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heavy with or as if with moisture

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