Etymologically
Log in

rodent

This is the current revision of this entry, as edited by bogdan on 1 November 2026 at 03:53. This address is a permanent link to this version.
Changes in this edit History

Pronunciation

  • UK: /ˈɹəʊdənt/[1]
  • US: /ˈɹoʊdənt/[1]

Etymology

It is borrowed from Latin rōdēns (“gnawing”), the present participle of rōdō (“to gnaw, eat away, erode”).[2][3][4][5][6] The zoological senses follow New Latin Rodentia, the scientific name of the order,[2][7][8][6] and the use for a despicable person follows the same figurative use of the word for a rat.[2] Klein sees the Latin verb as an ablaut variant of rādō (“to scrape”), the source of raze.[5][9] Its further origin is uncertain: Etymonline and the American Heritage Dictionary point to Proto-Indo-European *rēd- (“to scrape, scratch, gnaw”),[8][6] and Merriam-Webster to a root that also gave Hittite ardu- (“to saw off”) and a Sanskrit verb meaning to bite or gnaw.[7][2] Etymonline calls a connection with rat uncertain.[8] The same verb is behind erode, corrode and rostrum.[10][5]

Earliest recorded meaning

Acrid, corrosive, as an adjective: 1633, in Gutta Podagrica, a sense now obsolete.[2] Etymonline also dates the adjective "gnawing" to the 1630s.[8]

Semantic evolution

The word began as an adjective meaning "gnawing, eating away", and the zoological use came only with the order name Rodentia: the adjective "of the gnawing mammals" and the noun for such a mammal are both recorded from 1830,[2][7] Etymonline dating the noun to 1828[8] and Barnhart to 1835, with the adjective from 1833.[11][3] The older idea of eating away survives in medicine, in the rodent ulcer, a slow-growing malignant tumour of the face,[12][10] and in a rare poetic use for the sea or the air wearing things away (1874).[2] In 1889 Randolph Churchill's speeches show the word as an insult for a contemptible person, after the figurative use of rat.[2]

Timeline

  • 1633 – adjective, acrid, corrosive (now obsolete).[2]
  • 1830 – adjective, of the gnawing mammals of the order Rodentia; noun, such a mammal.[2][7] Etymonline dates the noun to 1828.[8]
  • mid 19th century – adjective, in medicine, of a slowly spreading ulcer of the face.[12]
  • 1874 – of the sea or the air, wearing things away (poetic, now rare).[2]
  • 1889 – noun, a despicable or worthless person.[2]

Meanings

Noun

  1. A mammal of the order Rodentia, such as a mouse, rat, squirrel or beaver, with incisor teeth that keep growing and are used for gnawing: A rodent had chewed through the cable in the attic.[13][7][2][12]
  2. A small mammal that resembles one, such as a shrew or a pika.[7]
  3. (derogatory) A despicable or worthless person.[2]

Adjective

  1. Of or relating to rodents; of teeth, fitted for gnawing.[2][7][12]
  2. Gnawing or eating away.[7][12]
  3. (medicine) Of an ulcer of the face: slowly eating into the tissue, as a malignant tumour.[12][10]

Word family

  • rodentlike
  • rodenticide

References

  1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h i j k l m n o Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
  3. ^ a b Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
  4. ^ Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
  5. ^ a b c Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
  6. ^ a b c The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
  7. ^ a b c d e f g h Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  8. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  9. ^ Weekley, Ernest (1921), An Etymological Dictionary of Modern English, London: John Murray
  10. ^ a b c Cresswell, Julia (2021), Oxford Dictionary of Word Origins, 3rd ed., Oxford: Oxford University Press
  11. ^ Barnhart, Robert K., ed. (1995), The Barnhart Concise Dictionary of Etymology, New York: HarperCollins
  12. ^ a b c d e f Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
  13. ^ Collins English Dictionary (2023), Glasgow: HarperCollins