magnesium

noun

mag·​ne·​sium mag-ˈnē-zē-əm How to pronounce magnesium (audio)
-zhəm
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Epsom salt actually can make a lawn greener, but only if what the lawn was lacking in the first place was magnesium. — David Beaulieu, The Spruce, 26 June 2026 Sourdough can also provide minerals such as iron and magnesium. — Daryl Austin, USA Today, 28 June 2026 Flax, chia, pumpkin, sunflower, sesame, and hemp seeds are rich in fiber, magnesium, healthy fats, and antioxidants that support heart health. — Jillian Kubala, Health, 25 June 2026 Occasionally, a lack of iron, phosphorus, potassium, or magnesium can also cause leaves to yellow. — Andy Wilcox, Better Homes & Gardens, 27 June 2026 See All Example Sentences for magnesium

Word History

Etymology

New Latin, from magnesia

First Known Use

1812, in the meaning defined above

Time Traveler
The first known use of magnesium was in 1812

Phrases Containing magnesium

Rhymes for magnesium

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Browse Nearby Words

magnesite
magnesium
magnesium bomb
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Cite this Entry

“Magnesium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/magnesium. Accessed 7 Jul. 2026.

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Kids Definition

magnesium

noun
mag·​ne·​sium mag-ˈnē-zē-əm How to pronounce magnesium (audio)
-zhəm
: a silver-white metallic element that is light and easily worked, burns with a dazzling light, and is used in making lightweight alloys see element

Medical Definition

magnesium

noun
mag·​ne·​sium mag-ˈnē-zē-əm How to pronounce magnesium (audio) -zhəm How to pronounce magnesium (audio)
: 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

More from Merriam-Webster on magnesium

Nglish: Translation of magnesium for Spanish Speakers

Britannica.com: Encyclopedia article about magnesium

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