magnesium oxide

noun

: a white highly infusible compound MgO used especially in refractories, cements, insulation, and fertilizers, in rubber manufacture, and in medicine as an antacid and mild laxative

Examples of magnesium oxide in a Sentence

Recent Examples on the Web

Batteries made with magnesium are less flammable because a protective layer of magnesium oxide covers the metal. —IEEE Spectrum, 7 Nov. 2014

Magnesium supplements usually contain only one type of magnesium, such as magnesium oxide. —Karen Berger, Verywell Health, 30 May 2025

However, magnesium oxide appears to have better laxative effects and is more widely studied for this purpose.24 How Does Magnesium Chloride Compare to Other Forms? —Emmanuella Ogbonna, Health, 14 May 2025

Magnesium supplements are available in many forms, like magnesium oxide, chloride, and sulfate.2 Magnesium citrate is the most effective form for muscle pain because the body can absorb and break down magnesium citrate better than other forms. —Kirstyn Hill, Pharmd, Mph, Health, 30 Apr. 2025

Word History

First Known Use

1866, in the meaning defined above

Rhymes for magnesium oxide

• acetaldehyde
• acetanilide
• arabinoside
• cycloheximide
• cyclophosphamide
• diethylamide
• dinucleotide
• ferricyanide
• ferrocyanide
• glutaraldehyde
• glyceraldehyde
• hydroperoxide

Kids Definition

magnesium oxide

noun

: a white earthy solid that consists of magnesium and oxygen and is used especially in fertilizers and rubber, as a mild laxative, and against acid in the stomach

Medical Definition

magnesium oxide

noun

: a white highly infusible compound MgO used especially in refractories, cements, insulation, and fertilizers, in rubber manufacture, and in medicine as an antacid and mild laxative