caudal

Etymology

It is borrowed from New Latin caudālis,^{[2][3][4][5][6][7]} formed from Latin cauda (“tail”) and the adjective suffix -ālis,^[8][5] which corresponds to English -al.^[4][9] Etymonline and Barnhart call the origin of cauda unknown or uncertain.^[9][4] De Vaan reconstructs Proto-Italic *kaud-ā- (“part, tail”) and Proto-Indo-European *keh₂u-d- (“cleaved, separate”), and suggests that the tail was named as the loose "part" of the animal, from the same root as the verb cūdō.^[10] Klein similarly takes the first sense to be "a piece cut off", relates the word to caudex (“a block of wood”), and refers to hew.^[11] The Latin word is also the source of coda, coward, cue and queue.^[11][5]

Earliest recorded meaning

Of or belonging to the tail, situated in or near it: 1661, in R. Lovell's Panzoologicomineralogia.^[2][4][5] Etymonline gives the 1660s.^[9]

Semantic evolution

The adjective has remained a term of anatomy and zoology for what is at or near the tail, and was extended to the hind or posterior part of the body in general.^[7][5][12] In upright animals such as humans this direction corresponds to below, so the American Heritage Dictionary also gives "situated beneath; inferior".^[13][1] From 1831, in a translation of Cuvier's Animal Kingdom, it was used as a noun for a caudal fin, vertebra or the like.^[2][7]

Timeline

• 1661 – of or belonging to the tail.^[2][4][5]
• 1831 – noun, a caudal fin, vertebra or other caudal part.^[2]

Meanings

Adjective

1. Of, relating to, or forming a tail: the caudal fin of a trout.^[5][13][2]
2. Situated in or directed toward the hind part of the body; posterior.^[5][13][12]
3. (anatomy) In humans, situated below; inferior.^[13][1]
4. Resembling a tail.^[13][2]

Noun

1. A caudal part, such as a fin, scale or vertebra.^[5][7][2]

Word family

• caudally
• postcaudal
• precaudal
• caudal fin

Related words

• queue
• caudate
• caudex
• coda
• coward
• cue

References

1. ^ a b c 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. ^ a b c d e Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
5. ^ a b c d e f g h i Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
6. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
7. ^ 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
8. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
9. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
10. ^ de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill
11. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
12. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins
13. ^ a b c d e The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin