magma

Etymology

It is borrowed from Latin magma (“dregs of an unguent”),^[2][3][4][5] from Ancient Greek μάγμα (mágma, “thick unguent, kneaded mass”),^[2][3][6][7] from μάσσω (mássō, “to knead, press into a mould”),^[6][2][8] from Proto-Indo-European *mag- (“to knead, fashion, fit”).^[3][5] The OED thinks the Greek verb perhaps ultimately cognate with make,^[2] and Merriam-Webster and Barnhart relate it to mingle.^[9][4] The geological sense appears to have been borrowed from French magma, where it was coined by Durocher in his “Essai de pétrologie comparée” (1857); French had used the word in pharmacology since the late 17th century.^[2]

Earliest recorded meaning

The dregs left after a semi-liquid substance has been pressed or evaporated: about 1440, in an English translation of Palladius on husbandry.^[2] Barnhart dates it to probably 1440,^[4] Etymonline to the mid 15th century,^[3] and Dictionary.com to 1400–50.^[7]

Semantic evolution

The sense "dregs" lasted until the mid 19th century.^[2][10] From 1681 the word was used for any pasty mixture of mineral or organic matter,^[2][8] and in 18th-century medicine for a thick salve;^[2] in pharmacy it later meant a thick suspension of a substance in water, a "milk".^[2][11] The geological sense, molten rock beneath the earth's crust from which igneous rocks form, is first recorded in 1865,^[2][4] though Etymonline finds it by 1859.^[3] The figurative sense of a confused mass of something dates from 1928.^[2][9]

Timeline

• c. 1440 – dregs left after pressing or evaporating (obsolete by 1857).^[2]
• 1681 – a pasty mixture of mineral or organic substances.^[2]
• 1749 – a thick ointment or salve (obsolete by 1848).^[2]
• 1865 – in geology, molten rock beneath the earth's crust.^[2][4] Etymonline dates it to 1859.^[3]
• 1911 – a thick suspension in water.^[2]
• 1928 – figuratively, a confused mass.^[2]

Meanings

Noun

1. In geology, hot molten rock beneath the earth's crust, which cools to form igneous rock and erupts at the surface as lava.^[11][2]
2. A thin paste, or a suspension of a finely divided solid in a liquid.^[11][9][2]
3. Something resembling magma; a confused mass.^[9][2]
4. (obsolete, c. 1440–1857) Dregs or sediment.^[2][9][10]

Word family

• magmatic
• magmatism

Related words

• mass
• macerate
• make
• mingle

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q r s t u v Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c d e Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
5. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
6. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
7. ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
8. ^ a b Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
9. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
10. ^ a b Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
11. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins