thoracic

Etymology

It is borrowed from Medieval Latin thōrācicus,^[2][3][4] from a Greek adjective formed from Ancient Greek θώραξ (thṓrāx, “breastplate, chest”),^[2][3][5] the source of thorax.^[6][2] Merriam-Webster Unabridged derives it instead from French thoracique,^[7] and the OED notes that Blount took it from an obsolete French thorachique, found in Ambroise Paré and in Cotgrave.^[2] Etymonline allows either a formation from the stem of thorax with -ic or the Medieval Latin word.^[6] The Greek noun has no etymology and is probably a loanword;^[6] Beekes takes its medical sense, the trunk of the body, as secondary to "cuirass, armour".^[6]

Earliest recorded meaning

Of, belonging to or contained in the chest: 1656, in Thomas Blount's Glossographia.^[2] Merriam-Webster Unabridged dates the word to about 1658,^[7] and Etymonline to the 1650s.^[6]

Semantic evolution

The word stayed a technical term of anatomy and zoology, and was extended as zoologists adopted thorax for the middle body segment of insects and crustaceans (1817).^[2] In the Linnaean classification, fishes whose ventral fins sit directly under the pectorals were called thoracic from 1769,^[2][7] and since 1828 the word has also been a noun for such a fish.^[2] In medicine it came to cover diseases of the chest region and its organs.^[3]

Timeline

• 1656 – of or in the chest.^[2]
• 1769 – of fishes, having the ventral fins under the pectoral fins.^[2]
• 1817 – of or forming part of the thorax of an insect or crustacean.^[2]
• 1828 – noun, a thoracic fish.^[2]
• 1842 – noun, a thoracic organ or structure.^[2]

Meanings

Adjective

1. Of, relating to, located in or affecting the thorax or chest: thoracic surgery.^[7][8][2]
2. Of or forming part of the thorax of an insect or crustacean.^[2]
3. Of a pelvic fin, placed under the pectoral fin and joined to the pectoral girdle.^[7][2]

Noun

1. A thoracic organ or structure.^[2]

Word family

• thoracically
• cardiothoracic
• intrathoracic
• nonthoracic
• transthoracic
• mesothoracic
• subthoracic
• thoracic duct

Related words

• thorax

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
4. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
5. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
6. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
7. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ Collins English Dictionary (2023), Glasgow: HarperCollins