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

Some testing companies will come out, test for everything under the sun, and may find an alarming level of another mineral like calcium or magnesium. —Karl Schneider, IndyStar, 31 Mar. 2026

Most side effects reported with magnesium are gastrointestinal (GI), including nausea, diarrhea, and stomach cramps. —Kirstyn Hill, Health, 31 Mar. 2026

Durabook has unveiled the Z14I-HG, a fully rugged mobile workstation packing 682 TOPS (trillion operations per second) of AI power inside a magnesium-alloy shell built to survive everything from minus 29 °C (-20 °F) frozen tundra to plus 63 °C (145 °F) desert heat and direct sandstorm exposure. —Omar Kardoudi march 31, New Atlas, 31 Mar. 2026

Almost half of Americans do not get enough magnesium from diet alone, per Mayo Clinic — which may help explain the prevalence of 3 AM wake-ups. —Allison Palmer, Fort Worth Star-Telegram, 30 Mar. 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