tubercle
(ˈtjuːbək(ə)l)
[ad. L. tūberculum small swelling, boil, pimple, dim. of tūber, tuber2. Cf. obs. F. tubercle (Cotgr., 1611).]
A small tuber or body resembling a tuber.
1. Anat. and Zool. A small rounded projection or protuberance, as on a bone, or on the surface of the body in various animals.
Often with defining word, as the specific name of such a structure: e.g. conoid, cuneiform, genial, laminated, madreporic, optic, scalene (etc.) tubercle: see the adjs.
| 1578 Banister Hist. Man i. 17 To this Tubercle they [‘bones’ of the larynx] are inarticulated and knit. 1747 Gentl. Mag. Mar. 122/2 These creatures have several rows of tubercles on their bodies. 1846 F. Brittan tr. Malgaigne's Man. Oper. Surg. 133 A more or less projecting tubercle on the first rib, which gives attachment to the anterior scalenus. 1880 Barwell Aneurism iii. 29 Chassaignac's tubercle, the transverse process of the fifth cervical vertebra. |
2. Path. A small firm rounded swelling or nodule on the surface of the body or in a part or organ; spec. a mass of granulation-cells characteristic of tuberculosis; transf. the disease tuberculosis.
miliary tubercle: see miliary 1.
| 1661 Lovell Hist. Anim. & Min. 355 The tubercles of the lungs. 1710 T. Fuller Pharm. Extemp. 52 A Balsamick Decoction..dissipates Crude Tubercles. 1804 Abernethy Surg. Obs. Tumours 149 The ulcerated surface may heal, and leave an indurated knob or tubercle in the affected part. 1818 Art Preserv. Feet 3 The corn is technically termed ‘clavus pedum’, and considered as a tubercle without organization, proceeding from the substance of the epidermis, and originating in the tightness of shoes or boots. 1859 J. Tomes Dental Surg. (1873) 51 Tubercle does not appear to interfere with the progress of dentition. 1876 J. S. Bristowe The. & Pract. Med. (1878) 67 It is a..characteristic of tubercle that its specific cells very rapidly fall into degeneration. |
3. Bot. a. A small tuber, or a root-growth resembling a tuber, as in many orchids. b. A small wart-like swelling or protuberance on a plant.
| 1727–41 Chambers Cycl., Tuber, on Tubercle, in botany, a kind of round turgid root. 1756–7 tr. Keysler's Trav. (1760) IV. 349 A particular species..has large prickles growing on round tubercles. 1807 J. E. Smith Phys. Bot. 498 Fucus,..whose seeds are collected together in tubercles or swellings, of various forms and sizes. 1880 Gray Struct. Bot. iii. §3 (ed. 6) 60 Tubercles..are of a mixed..character between tubers and tuberous roots. |
4. attrib. and Comb., as tubercle-like, tubercle-infected adjs.; tubercle-bacillus, the species of bacillus which causes tuberculosis (also attrib.).
| 1866 Tate Brit. Mollusks iv. 165 A tubercle-like tooth [in a shell]. 1891 Cent. Dict. s.v. Tubercle, Tubercle-bacillus. 1897 Daily News 1 Apr. 3/4 Both assume the so-called tubercle-bacillus tint. 1898 Westm. Gaz. 3 Nov. 9/2 If the Council can prevent the sale of tubercle-infected milk. 1913 Times 6 Aug. 8/4 Microscopical examination of milk and tubercle bacillus by analytical methods. |