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

Chicken is a rich source of protein and essential nutrients like magnesium, selenium, and iron that many diets lack. —Lindsey Desoto, Health, 13 Nov. 2025

The Different Forms of Magnesium Choosing the form of magnesium to take should be based on personal preference. —Cristina Mutchler, Verywell Health, 13 Nov. 2025

Your water contains minerals like magnesium and calcium that collect in the bottom of the water heater. —Brandee Gruener, Southern Living, 2 Nov. 2025

Certain dietary supplements, such as the magnesium glycinate mentioned above, taurine, L-theanine, or herbal adaptogens such as rhodiola, can also be helpful. —Desireé Oostland, Vogue, 1 Nov. 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