axon

Etymology

It is borrowed from Ancient Greek ἄξων (áxōn, “axis, axle”),^[2][3][4][5] through New Latin axon according to Barnhart, Merriam-Webster Unabridged and Collins.^[6][7][8] Collins and Klein add the Greek senses "vertebra" and "axle".^[8][9][7] The Greek word is cognate with Latin axis,^[9][10] and Etymonline derives both from Proto-Indo-European *aks- (“axis”), also the source of Old English eax.^[5]

Earliest recorded meaning

The axis of the body: 1842, in the third edition of R. Dunglison's Medical Lexicon, which also has the nerve-cell sense.^[2]

Semantic evolution

The anatomical sense "body axis" fell out of use in the late 19th century (last recorded 1884),^[2][11] and the word was kept for the long process that carries impulses away from a nerve cell.^[2][11] Etymonline and Barnhart date that sense only to 1899,^[5][6] and Merriam-Webster Unabridged to 1895.^[7] The spelling axone is a less common variant.^[7][8][11]

Timeline

• 1842 – the axis of the body (obsolete by 1884).^[2][5]
• 1842 – the long process of a nerve cell that carries impulses away from it.^[2] Etymonline and Barnhart date this sense to 1899, and Merriam-Webster Unabridged to 1895.^[5][6][7]

Meanings

Noun

1. The long, thread-like extension of a nerve cell that carries nerve impulses away from the cell body, as opposed to the dendrites.^[8][7][2]
2. (obsolete, 1842–1884) The main axis of the body.^[2][11]

Word family

• axonal

Related words

• axis
• axle

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. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
4. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
5. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
6. ^ a b c Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
7. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ a b c d Collins English Dictionary (2023), Glasgow: HarperCollins
9. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
10. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
11. ^ a b c d Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press