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

Frequently Asked Questions What causes hard water stains in toilets? Toilets with water that contain a higher concentration of calcium and magnesium are more prone to hard water stains. —Ashlyn Needham, Southern Living, 25 Apr. 2025

These include calcium, magnesium, vitamin K, iron, phosphorus, zinc, and manganese. —Julie Marks, Verywell Health, 23 Apr. 2025

If your magnesium levels are normal or high, your kidneys will remove extra magnesium through your urine. —Kirstyn Hill, Pharmd, Mph, Health, 22 Apr. 2025

Indeed, just two small plums (100 grams), contain protein, calcium, magnesium, phosphorus, potassium, zinc, biotin, vitamin K, vitamin C and more than a gram of dietary fiber, per the U.S. Department of Agriculture. —Daryl Austin, USA Today, 22 Apr. 2025

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