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magnesia

Etymology and origin of the English word magnesia

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Pronunciation

  • IPA: /ˌmæɡˈniʒə/ (US)[1]

Etymology

It comes from Middle English magnasia,[2][3] from Medieval Latin magnesia,[3][2][4][5] from Ancient Greek Μαγνησία (Magnēsía), short for Magnēsía líthos “the Magnesian stone”, the lodestone,[2][4][5] named after Magnesia in Thessaly.[2][4] The American Heritage Dictionary instead names the city of Magnesia in Asia Minor,[3] and Merriam-Webster derives the chemical sense from New Latin magnes carneus “flesh magnet”, a white earth.[6] It is related to magnet.[4][1]

Earliest recorded meaning

In alchemy, a mineral held to be one of the ingredients of the philosopher's stone (about 1395, or about 1386 in the OED).[2][7][3][4]

Semantic evolution

In ancient times the same word was used for lodestone and for a black mineral used to clear glass, now called manganese dioxide;[4] English magnesia meant manganese from 1677.[7] In the 18th century a white powder sold in Rome as magnesia alba was used in medicine and cosmetics,[4][7] and in modern chemistry the name was fixed on magnesium oxide (1755).[7][6] Davy isolated the metal magnesium from it in 1808.[4]

Timeline

  • about 1386–95 – an alchemical mineral.[7][2]
  • 1677 – manganese, “black magnesia”.[7]
  • 1755 – magnesium oxide.[7][6]
  • 1808 – Davy isolates magnesium from it.[4]

Modern meaning

Noun

  1. Magnesium oxide, a white powder used in medicine as an antacid and laxative.
  2. Hydrated magnesium carbonate, a white powder long called magnesia in everyday use.

Word family

  • magnesian
  • magnesite
  • magnesium
  • milk of magnesia

References

  1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f Barnhart, Robert K., ed. (1995), The Barnhart Concise Dictionary of Etymology, New York: HarperCollins
  3. ^ a b c d The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin
  4. ^ a b c d e f g h i Harper, Douglas, Online Etymology Dictionary, https://www.etymonline.com
  5. ^ a b Random House Webster's Unabridged Dictionary (1999), 2nd ed., New York: Random House
  6. ^ a b c Merriam-Webster's Collegiate Dictionary (2003), 11th ed., Springfield, Mass.: Merriam-Webster
  7. ^ a b c d e f g Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press

Related etymologies

Cite this entry

“Magnesia.” Etymologically, 11 Oct. 2026, etymologically.com/en/magnesia. Accessed 11 Oct. 2026.

Last edited on . ·