magnesium

noun

: 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.
The calcium and magnesium dissolved in hard water are not what standard shower filters are built to capture. Ryan Brennan, Fort Worth Star-Telegram, 16 Sep. 2026 Whole-home ion-exchange systems are specifically designed to remove the calcium and magnesium responsible for hardness. Ryan Brennan, Miami Herald, 16 Sep. 2026 However, some stars collapse to form a white dwarf composed of oxygen, neon and magnesium. Robert Lea, Space.com, 16 Sep. 2026 Calcium and magnesium react with soap and leave behind a film that is harder to rinse away. Ryan Brennan, Kansas City Star, 15 Sep. 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

Browse Nearby Words

Cite this Entry

“Magnesium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/magnesium. Accessed 18 Sep. 2026.

Kids Definition

magnesium

noun
: 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

: 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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