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

The measurements identified 13 elements from this doomed object, including aluminum, carbon, chromium, cobalt, copper, iron, magnesium, manganese, nickel, silicon, sodium, strontium and titanium, in mostly Earth-like abundances. —Keith Cooper, Space.com, 24 Oct. 2025

Dates provide nutrients like potassium, magnesium, and vitamin B6 that support heart, bone, and brain health. —Maggie O'Neill, Verywell Health, 24 Oct. 2025

By adding elements like titanium, magnesium and calcium, the glass becomes even tougher and stronger than steel. —Kurt Knutsson, FOXNews.com, 23 Oct. 2025

Since orange trees are heavy feeders, look for a fertilizer that contains more nitrogen, such as a 2-1-1 or 3-1-1 nitrogen-phosphorus-potassium (NPK) ratio, as well as micro nutrients like magnesium, zinc, and iron. —Karen Brewer Grossman, Southern Living, 22 Oct. 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