epidural

Etymology

It is formed from English epi- + dura + -al,^{[2][3][4][5][6]} the second part standing for dura mater;^[2][5] Merriam-Webster Unabridged and Webster's Third analyse it as epi- and dural.^[7][8] The prefix is from Ancient Greek ἐπί (epí, “upon”).^[5][9] The membrane's name is Medieval Latin dūra māter (“hard mother (of the brain)”), a translation of an Arabic phrase, with dūra, the feminine of Latin dūrus (“hard”).^[10][2]

Earliest recorded meaning

Situated on or outside the dura mater, or affecting it: 1882, in E. A. Schäfer's part of Quain's Elements of Anatomy.^[2] Etymonline dates the adjective to 1873,^[5] Dictionary.com to 1880–85.^[6]

Semantic evolution

The adjective was at first anatomical, of the space and structures just outside the dura mater, as in an epidural abscess.^[2][7] It came into everyday use with epidural anaesthesia, an injection of a local anaesthetic into the epidural space of the lower spine, used especially to relieve pain in childbirth.^[3][11][5] The noun, short for such an injection, is attested by 1966 in Etymonline,^[5] while the OED (in the Guardian) and Merriam-Webster Unabridged date it to 1970.^[2][7]

Timeline

• 1882 – adjective, situated on or outside the dura mater.^[2][7]
• 1966 – noun, an epidural injection.^[5]

Meanings

Adjective

1. Situated on or outside the dura mater, or given into the space outside it; extradural: an epidural haematoma.^[11][7][3]

Noun

1. An injection of a local anaesthetic into the space outside the dura mater of the lower spine, which numbs the lower part of the body, used especially in childbirth: She asked for an epidural early in labour.^[7][11][2]
2. The anaesthesia produced in this way.^[11]

Related words

• dura mater
• dural
• subdural

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
4. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
5. ^ a b c d e f g Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
6. ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
7. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ Gove, Philip Babcock, ed. (1961), Webster's Third New International Dictionary of the English Language, Unabridged, Springfield, Mass.: G. & C. Merriam
9. ^ The Chambers Dictionary (2008), 11th ed., Edinburgh: Chambers Harrap
10. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
11. ^ a b c d Collins English Dictionary (2023), Glasgow: HarperCollins