a. (sb.). Also 7 thorachique, -cique. [ad. med.L. thōrācic-us, a. Gr. θωρᾱκικ-ός, f. θώρᾱξ, θωρᾱκ-: see THORAX and -IC. In Blount from obs. F. thorachique (A. Paré in Cotgr.).]
1. Anat. Of, pertaining to, or contained in the thorax; pectoral.
Thoracic aorta (also called pectoral aorta), that part of the aorta which traverses the thorax. Thoracic artery, any one of the branches arising from the axillary artery. Thoracic cage, the skeleton of the thorax with its ligaments (Billings, 1890). Thoracic cavity, the space enclosed by the ribs, spine, and diaphragm, containing the heart, lungs, etc. Thoracic duct, the main trunk of the lymphatic system, through which the chyle and lymph are conveyed to the blood. Thoracic limb, in a vertebrate, a fore-limb; in man, the arm; in quadrupeds, the fore-leg: in birds, the wing; in fishes, a thoracic or pectoral fin; in invertebrates, a member appended to the thorax. Thoracic vertebra, a vertebra which articulates with a rib; a dorsal vertebra.
1656. Blount, Glossogr., Thorachique,… belonging to the breast or stomack. Ibid., s.v. Vein.
1658. Phillips, Thoracique,… belonging to the stomack or brest.
1727–41. Chambers, Cycl., s.v., The thoracic arteries…. Thoracic veins…. Thoracic duct … is … a continuation of the exit or mouth of the receptaculum chyli.
1793. Beppoes, Lett. Darwin, 56. No sooner does it touch the lungs than … the functions of all the thoracic organs go on easily and pleasantly again.
1793. M. Baillie, Morb. Anat., Pref. (1807), 10. The thoracic and abdominal viscera.
1876. Bristowe, The. & Pract. Med. (1878), 13. In our own country, thoracic inflammations are most frequent during the cold seasons of the year.
b. Pertaining to, attached to, or forming part of the thorax (of an insect or crustacean).
1817. Kirby & Sp., Entomol. (1818), II. 413. The light emitted by the two thoracic tubercles alone is so considerable [etc.].
1880. Huxley, Crayfish, i. 22. The crayfish … walks by means of the four hinder pairs of thoracic limbs.
2. Ichthyol. Having the ventral fins situated directly beneath the pectoral; belonging to the Thōrācicī, the third order of fishes in the Linnæan system. Cf. ABDOMINAL a. 3.
1769. Pennant, Zool., III. 216. That section of bony fish, termed Thoracic.
1774. Goldsm., Nat. Hist. (1862), II. III. i. 294. The ventral fins placed directly under the pectoral fins,… and then it is called a Thoracic fish.
1854. Owen, Skel. & Teeth, in Orr’s Circ. Sc. I. Org. Nat., 183. The fins called ‘ventral’ … indicate by their position the orders of fishes called ‘abdominal,’ ‘thoracic,’ and ‘jugular,’ by Linnæus.
3. Having a thorax (as a distinguishing character); belonging to the Thoracica, a sub-order of cirripeds, in which the body consists of six thoracic segments, with a rudimentary abdomen.
1891. in Cent. Dict.
4. As a specific distinction in Nat. Hist.: Having the thorax conspicuously marked or colored.
c. 1812. Shaw, Natur. Misc., XXII. 969. Thoracic Wagtail [Motacilla thoracica].
1819. Stephens, in Shaw, Gen. Zool., XI. 322. Thoracic Francolin [Francolinus thoracicus].
5. Comb., as thoracic-abdominal a., of the combined thorax and abdomen.
1835–6. Todd’s Cycl. Anat., I. 214/1. A … band which commences at the thoracic-abdominal constriction.
1854. Owen, Skel. & Teeth, in Orr’s Circ. Sc. I. Org. Nat., 191. The ribs … do not encompass the thoracic-abdominal cavity.
B. sb. † 1. A medicine acting on the thorax; a pectoral. Obs.
[1706. Phillips (ed. Kersey), Thoracica, medicines proper for Diseases of the Breast.]
1710. T. Fuller, Pharm. Extemp., 249. In a word it is a most excellent Thoracic.
2. A thoracic fish: see 2 above.
1828. Webster, Thoracics,… an order of bony fishes,… the ventral fins are placed underneath the thorax, or beneath the pectoral fins.
3. A thoracic organ or structure.
1857. Dunglison, Med. Lex., s.v., First of the Thoracics, mammary superior external artery.
