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

The advice says drinking water high in minerals is better for constipation than tap water, and magnesium oxide supplements are good for improving symptoms.

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

Treatment with hydrochloric acid removes the magnesium 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