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

This is why certain forms, like magnesium citrate or magnesium oxide, are often used as laxatives. — Sarah Jividen, Verywell Health, 23 Oct. 2026

The sack held more than a ton of a feedstock made largely of magnesium oxide. — Alec Luhn, Scientific American, 20 Oct. 2026

The other bit of information from the chemistry of the eruption is from magnesium oxide, which provides an indication of the temperature of the magma. — John Timmer, ArsTechnica, 9 Oct. 2026

When testing these candidates in the lab, magnesium oxide stood out as the top performer. — Mrigakshi Dixit, Interesting Engineering, 17 July 2026

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