magnesium oxide

American  

noun

Chemistry.

1. magnesia.

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magnesium oxide British  

noun

1. Also called: magnesia.  a white tasteless substance occurring naturally as periclase: used as an antacid and laxative and in refractory materials, such as crucibles and fire bricks. Formula: MgO

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Etymology

Origin of magnesium oxide

First recorded in 1905–10

Compare meaning

How does magnesium-oxide compare to similar and commonly confused words? Explore the most common comparisons:

• magnesium hydroxide vs. magnesium oxide
• magnesium vs. magnesium oxide
• magnesium oxide vs. magnesium sulfate

Example Sentences

See Examples For:

magnesium oxide

And that's why taking magnesium oxide supplements was found to have lots of benefits, according to the research.

From BBC ● Oct. 13, 2025

The magnesium formed a thin layer of magnesium oxide on the tantalum surface that appears to keep oxygen from getting through.

From Science Daily ● Feb. 5, 2024

That reaction would leave magnesium oxide powder, which when spread thin would rapidly react with CO2 from the atmosphere, re-forming magnesite, completing a cycle that could be repeated over and over.

From Science Magazine ● Sep. 3, 2020

The oxides of the alkali metals have little industrial utility, unlike magnesium oxide, calcium oxide, and aluminum oxide.

From Textbooks ● Feb. 14, 2019

The cement shall not contain more than 1.75% of anhydrous sulphuric acid, nor more than 4% of magnesium oxide.

From Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 Federal Investigations of Mine Accidents, Structural Materials and Fuels. Paper No. 1171 by Wilson, Herbert M.