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

The research also found that supplements such as psyllium fiber, certain probiotics, and magnesium oxide may provide additional relief.

From Science Daily • Oct. 22, 2025

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

From BBC • Oct. 13, 2025

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

It is virtually a compound of the two oxides, aluminum oxide and magnesium oxide.

From A Text-Book of Precious Stones for Jewelers and the Gem-Loving Public by Wade, Frank Bertram