sea·​wa·​ter | \ ˈsē-ˌwȯ-tər How to pronounce seawater (audio) , -ˌwä-\

Definition of seawater

: water in or from the sea

Examples of seawater in a Sentence

Recent Examples on the Web

The roar of the ventilators in the galley quit as Joseph Sellar, a stocky 25-year-old Coast Guard culinary specialist from New Hampshire, watched seawater explode from the ceiling. Los Angeles Times, "Meet the neglected 43-year-old stepchild of the U.S. military-industrial complex," 2 Aug. 2019 Energy gets recovered during the freshwater and seawater flushes, with no upfront investment or charging required. Fox News, "Clean energy? Researchers develop technology to harness power from freshwater and seawater," 31 July 2019 Netthat the compound, made by using epoxy as a base and incorporating mango leaf extracts in a substrate of amorphous silica, achieved 99% inhibition of corrosion in commercial steel when immersed in a saline medium to mimic seawater. Ranjit Devraj, Quartz India, "Mango leaves: Indian scientists’ solution to a $2.5 trillion global shipping problem," 24 July 2019 Two for one special To put that into context, removing that much seawater from the ocean would lower global sea level by about 2 millimeters per year. Scott K. Johnson, Ars Technica, "Running the numbers on an insane scheme to save Antarctic ice," 20 July 2019 Breweries and distilleries are also opening at a significant pace, with pro surfer Taj Burrows even designing his own beer using seawater at Caves Road Collective. Kathryn Romeyn, The Hollywood Reporter, "Hollywood's Travel Guide to Western Australia," 16 July 2019 San Francisco tourists slosh through seawater at the Embarcadero. Aaron Gilbreath, Longreads, "Can Coastal California Adapt to Climate Change?," 15 July 2019 That’s because pufferfish can lock seawater inside their guts in order to keep their shape if squeezed or bitten, while the gill chambers of coffinfish are essentially open, meaning the water would just leak out if they were bitten. Joshua Rapp Learn, National Geographic, "This odd deep-sea fish can hold its breath for four minutes," 27 June 2019 That’s far higher than the radioactivity of the surrounding seawater, which was measured at .001 becquerels per liter. Kyle Mizokami, Popular Mechanics, "30 Years Later, a Sunken Soviet Sub Is Still Leaking Radioactivity," 12 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'seawater.' 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 seawater

before the 12th century, in the meaning defined above

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Statistics for seawater

Last Updated

8 Aug 2019

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Time Traveler for seawater

The first known use of seawater was before the 12th century

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More Definitions for seawater



English Language Learners Definition of seawater

: water in or from the sea


sea·​wa·​ter | \ ˈsē-ˌwȯ-tər How to pronounce seawater (audio) , -ˌwä-\

Kids Definition of seawater

: water in or from the sea

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More from Merriam-Webster on seawater

Rhyming Dictionary: Words that rhyme with seawater

Spanish Central: Translation of seawater

Nglish: Translation of seawater for Spanish Speakers Encyclopedia article about seawater

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