thorax

Etymology

It is inherited from Middle English thorax, also thorace and thoracis,^[2][3] borrowed from Latin thōrāx (“breastplate; chest”),^[4][5][6][3] from Ancient Greek θώραξ (thṓrāx, “breastplate, cuirass; chest”).^[4][5][6][7] The MED adds thorāca as a source.^[2] Etymonline calls the Greek word of unknown origin.^[5] Beekes holds that it is a technical word without an etymology, probably a loan and most probably Pre-Greek, and compares Latin lōrīca as another loanword; he rejects a link with a Sanskrit word for a container.^[8] Older works took another view: Skeat explained it as literally a defender, from a Sanskrit root meaning to carry or keep,^[9] and Klein and Merriam-Webster tentatively compare a Sanskrit verb meaning "holds", which Klein derives from Proto-Indo-European *dher- (“to hold”).^[10][11]

Earliest recorded meaning

The part of the body enclosed by the ribs: about 1400, in the Middle English translation of Lanfranc's surgery.^[4][2] Barnhart dates the word to 1392,^[6] Etymonline to the late 14th century,^[5] Merriam-Webster to the 15th,^[11] and Hoad and Collins to the 16th.^[7][12]

Semantic evolution

In Greek, the armour came first: the word means a cuirass in the Iliad and the trunk or chest only from the Hippocratic writers, and Beekes considers the medical meaning probably secondary.^[8][5] English borrowed the medical sense, which at first could cover the breastbone, the front of the chest, the chest cavity or the upper torso.^[2] Zoologists applied it from 1753 to the middle section of an arthropod's body, between the head and the abdomen.^[4] The original Greek sense, a cuirass or corselet, appears in English only in 1842, in writing about ancient Greece.^[4]

Timeline

• c. 1400 – the chest of the body, in Lanfranc's Cirurgie.^[4][2] Barnhart has the word from 1392.^[6]
• 1753 – the middle region of an arthropod's body.^[4]
• 1842 – an ancient Greek cuirass or corselet.^[4]

Meanings

Noun

1. The part of the body of a human or other mammal between the neck and the abdomen, enclosed by the ribs and breastbone; the chest.^[11][12][4]
2. The middle division of the body of an insect or other arthropod, which carries the legs and any wings.^[12][11][4]
3. (ancient Greek history) A cuirass or corselet.^[4]

Word family

• cephalothorax
• hydrothorax
• mesothorax
• metathorax
• pneumothorax
• prothorax
• pyothorax
• thoracic

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ 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)
3. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
4. ^ a b c d e f g h i j k Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
5. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
6. ^ a b c d Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
7. ^ a b Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
8. ^ a b Beekes, Robert S. P. (2010), Etymological Dictionary of Greek, with the assistance of Lucien van Beek, Leiden Indo-European Etymological Dictionary Series 10, Leiden; Boston: Brill
9. ^ Skeat, Walter W. (1911), A Concise Etymological Dictionary of the English Language, new ed., Oxford: Clarendon Press
10. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
11. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
12. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins