mag·​ne·​sium | \mag-ˈnē-zē-əm, -zhəm\

Definition of magnesium 

: a silver-white malleable ductile light metallic element that occurs abundantly in nature and is used in metallurgical and chemical processes, in photography, signaling, and pyrotechnics because of the intense white light it produces on burning, and in construction especially in the form of light alloys — see Chemical Elements Table

Examples of magnesium in a Sentence

Recent Examples on the Web

Low in calories and fat and cholesterol-free, mushrooms contain a modest amount of fiber and over a dozen minerals and vitamins, including copper, potassium, magnesium, zinc and a number of B vitamins such as folate. Roni Caryn Rabin, New York Times, "What Is the Health and Nutritional Value of Mushrooms?," 19 Jan. 2018 Usually the nurses administer a version of the Myers Cocktail, a mix of B and C vitamins, potassium, magnesium, calcium, and amino acids delivered with an intravenous needle. Jamie Rosen, Town & Country, "Is the Wellness IV the Next Big Thing in Beauty?," 15 Aug. 2018 The body is made out of magnesium with slightly more rounded edges than other Surface computers. Dieter Bohn, The Verge, "Microsoft Surface Go review: a little goes a long way," 7 Aug. 2018 This tropical fruit contains two important electrolytes, potassium and magnesium, plus antioxidants that prevent inflammation and actinidin, an enzyme that helps with protein digestion. NBC News, "8 summer superfoods to eat after a tough workout," 11 July 2018 Additional amounts of magnesium, B-complex vitamins, B-12, biotin, glutathione, zinc and anti-nausea drug Zofran are also barreling through my bloodstream. Craig Hlavaty, Houston Chronicle, "Feeling the drip, drip, drip of the mobile IV craze," 13 June 2018 Tap water has all kinds of things in it that can affect your skin, such as fluoride, calcium, and magnesium. Dr. Leslie Baumann, miamiherald, "How to use a skin cleanser and see results," 3 July 2018 After three to eight days, the magnesium degrades, allowing the device to float to the surface where researchers can recover it. Jason Daley, Smithsonian, "Researchers Record the Sounds of the Elusive Narwhal," 15 June 2018 Better regulate your blood pressure: The magnesium content assists with muscle contraction and cognition too. Jaclyn London, Ms, Rd, Cdn, Good Housekeeping, "It's Official: Cauliflower Is Just as Good for You as Colorful Veggies," 31 May 2018

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

1812, in the meaning defined above

History and Etymology for magnesium

New Latin, from magnesia

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Statistics for magnesium

Last Updated

4 Dec 2018

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Time Traveler for magnesium

The first known use of magnesium was in 1812

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More Definitions for magnesium



English Language Learners Definition of magnesium

: a silver-white metallic element that produces a very bright white light when it burns


mag·​ne·​sium | \mag-ˈnē-zē-əm, -ˈnē-zhəm\

Kids Definition of magnesium

: a silvery white metallic chemical element that is lighter than aluminum and is used in lightweight alloys


mag·​ne·​sium | \mag-ˈnē-zē-əm, -zhəm \

Medical Definition of magnesium 

: a silver-white light malleable ductile metallic element that occurs abundantly in nature (as in bones and seeds and in the form of chlorophyll in the green parts of plants) and is used in metallurgical and chemical processes, in photography, in signaling, and in the manufacture of pyrotechnics because of the intense white light it produces on burning, and in construction especially in the form of light alloys symbol Mg — see Chemical Elements Table

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More from Merriam-Webster on magnesium

Rhyming Dictionary: Words that rhyme with magnesium

Spanish Central: Translation of magnesium

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

Comments on magnesium

What made you want to look up magnesium? Please tell us where you read or heard it (including the quote, if possible).


the figure or shape of a crescent moon

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