Definition of magnesia in English:


Pronunciation /maɡˈniːʒə//maɡˈniːʃə//maɡˈniːsɪə//maɡˈniːzɪə/


mass nounChemistry
  • 1Magnesium oxide.

    Chemical formula: MgO

    • ‘But neither of these qualifies: lime is calcium oxide, a compound of calcium and oxygen, and magnesia is magnesium oxide.’
    1. 1.1 Hydrated magnesium carbonate used as an antacid and laxative.
      • ‘I had a colonoscopy last fall and the doctor said that I could take milk of magnesia as often as needed.’
      • ‘Or sometimes medicine such as milk of magnesia can be mixed with chocolate or strawberry-flavored milk.’
      • ‘My doctor suggested I use milk of magnesia to combat constipation.’
      • ‘Some further experimentation, and some work with a pill-pressing machine, provided Astor with two part-filled bottles, one labelled milk of magnesia and the other labelled soluble aspirin.’
      • ‘Another option to help reduce discomfort and speed healing is dabbing a mixture of equal parts water and hydrogen peroxide directly on the sore, followed by a bit of milk of magnesia.’


Late Middle English (referring to a mineral said to be an ingredient of the philosopher's stone): via medieval Latin from Greek Magnēsia, denoting a mineral from Magnesia in Asia Minor.