magˈnēsh]ə, maig-, -ēzh] sometimes ]ēə\ noun
( -s )
Etymology: Middle English, from Medieval Latin, from Greek magnēsia, any of several ores and amalgams, from feminine of Magnēs of Magnesia, ancient city in Asia Minor
1. obsolete : an ingredient of the philosophers' stone sometimes described as a plasmic saltish fluid or gum composed of the four elements
2. archaic : manganese
3.
a. : a white highly infusible solid consisting of magnesium oxide MgO that occurs naturally as periclase, is obtained in various forms (as a light bulky slightly alkaline reactive powder or a heavier refractory solid) usually by calcining magnesite or a basic magnesium carbonate or magnesium hydroxide, and that is used chiefly in making firebrick and other refractories, in magnesium oxychloride cements, insulation, fertilizers, and rubber, and in medicine and pharmacy especially as an antacid and mild laxative
b. : magnesium — not used systematically
carbonate of magnesia
citrate of magnesia
4. : magnesium carbonate — not used systematically