Etymologically
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em

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Pronunciation

Etymology

It is the name of the letter M, written as a word,[2][3] from the Latin name of the letter;[4] the Greek name was mu.[4] The printing unit is named from the letter M, since its width is about that of an em.[3][5]

Earliest recorded meaning

The name of the letter M: about 1200 in Etymonline,[4] the 13th century in Merriam-Webster.[6]

Semantic evolution

In printing it was originally the square body corresponding to the capital M of a given type,[4][7] hence a unit for measuring the amount of type set in a line or page, from the 18th century.[8][3] A pica em is the em of 12-point type, one sixth of an inch.[5][9] Compare en, the half of an em.[8] The em dash or em rule is a dash one em long.[10]

Timeline

  • c. 1200 – the name of the letter M.[4]
  • 18th century – the printing measure.[8][3]

Modern meaning

Noun

  1. The letter M or m.
  2. (printing) A unit of measure equal to the width of a square piece of type of a given size.
  3. (printing) Such a measure for 12-point type; a pica.

Word family

  • em dash
  • em quad

Usage notes

In dialects of Scotland, Ireland and England em was the unemphatic form of them, usually written ’em in standard spelling.[11]

References

  1. ^ Jones, Daniel (2011), Cambridge English Pronouncing Dictionary, 18th ed., ed. Peter Roach, Jane Setter and John Esling, Cambridge: Cambridge University Press
  2. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
  3. ^ a b c d Soanes, Catherine; Stevenson, Angus, eds. (2004), Concise Oxford English Dictionary, 11th ed., Oxford: Oxford University Press
  4. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  5. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins
  6. ^ Merriam-Webster's Collegiate Dictionary (2003), 11th ed., Springfield, Mass.: Merriam-Webster
  7. ^ Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
  8. ^ a b c Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
  9. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin
  10. ^ The Chambers Dictionary (2008), 11th ed., Edinburgh: Chambers Harrap
  11. ^ Wright, Joseph, ed. (1898–1905), The English Dialect Dictionary, 6 vols., Oxford: Henry Frowde; via EDD Online 4.0, University of Innsbruck (CC BY 4.0)