cornea

Etymology

It is borrowed from Medieval Latin cornea,^[2][3][4][5] short for cornea tēla (“horny web or tissue”),^[2][6][7][8] and later cornea tunica (“horny coating”),^[2][6][7][9] the feminine of Latin corneus (“horny”),^[2][5][6][9] from cornū (“horn”),^{[5][10][6][9]} from Proto-Indo-European *ker- (“horn; head”).^[10] Barnhart thinks the shortening was probably influenced by the earlier Old French cornee (1314).^[7] Klein and the Oxford Dictionary of Word Origins connect it with horn and with corn in the sense of a hardened patch of skin.^[9][11]

Earliest recorded meaning

The transparent front of the eyeball: before 1398, in Trevisa's translation of Bartholomew's De Proprietatibus Rerum, where it is one of two coats closing in the vitreous humour.^[3][7] The OED entry, not fully revised, begins only in 1527, in L. Andrewe's translation of Brunschwig.^[2]

Semantic evolution

The word has kept its anatomical meaning since Middle English; it is named for its horny consistency.^[10][2] Middle English also had corn and corne for it, as in Lanfranc before 1400, where it renders the Latin.^[3] Corneal is recorded from 1808,^[7][12] and in 1854 W. Mackenzie's treatise on diseases of the eye is the OED's first record of a further sense, a conical projection of the cornea.^[2] Merriam-Webster Unabridged also applies the word to the outer covering of the compound eyes of arthropods.^[4]

Timeline

• before 1398 – the transparent coat of the eyeball, in Trevisa.^[3][7]
• before 1400 – corn, the same part, in Lanfranc.^[3]
• 1854 – a conical projection of the cornea.^[2]

Meanings

Noun

1. The transparent, convex outer membrane at the front of the eyeball, covering the iris and pupil and admitting light: The surgeon made a tiny incision in the cornea.^[4][13][14]
2. The outer transparent covering of the compound eyes of arthropods.^[4]

Word family

• corneal
• corneitis
• ectocornea

Related words

• horn
• corn
• corneous

References

1. ^ 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 d e Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
4. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
5. ^ a b c The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
6. ^ a b c d Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
7. ^ a b c d e f Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
8. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
9. ^ a b c d Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
10. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
11. ^ Cresswell, Julia (2021), Oxford Dictionary of Word Origins, 3rd ed., Oxford: Oxford University Press
12. ^ Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
13. ^ Collins English Dictionary (2023), Glasgow: HarperCollins
14. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press