magnesium

noun

mag·​ne·​sium mag-ˈnē-zē-əm 

-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

Potassium was the most concentrated mineral in the ash, followed by sodium, calcium, phosphorus and magnesium. — Idaho Statesman, 17 Aug. 2026

Chia seeds are high in magnesium, fiber, and omega-3s, which may support sleep and reduce inflammation. — Kathleen Ferraro, Verywell Health, 17 Aug. 2026

Aston Martin says the Valen weighs up to 110 kg less than the core V12 platform, with extensive use of carbon fiber, aluminum, titanium and magnesium. — Matthew MacConnell, Forbes.com, 15 Aug. 2026

Patients should also ensure proper nutrition, following diets high in protein, calcium, vitamin D, and magnesium to promote muscle and bone health. — Jessica Starr, Fortune, 14 Aug. 2026

Word History

Etymology

New Latin, from magnesia

First Known Use

1812, in the meaning defined above

Phrases Containing magnesium

• magnesium carbonate
• magnesium chloride
• magnesium hydroxide
• magnesium oxide
• magnesium sulfate

Rhymes for magnesium

• caesium
• cesium
• trapezium

Kids Definition

magnesium

noun

mag·​ne·​sium mag-ˈnē-zē-əm 

-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  -zhəm 

: 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