from
The Collaborative International Dictionary of English v.0.48
Tubercle \Tu"ber*cle\, n. [L. tuberculum, dim. of tuber: cf. F.
tubercule, OF. also tubercle. See {Tuber}.]
[1913 Webster]
1. A small knoblike prominence or excrescence, whether
natural or morbid; as, a tubercle on a plant; a tubercle
on a bone; the tubercles appearing on the body in leprosy.
[1913 Webster]
2. (Med.) A small mass or aggregation of morbid matter;
especially, the deposit which accompanies scrofula or
phthisis. This is composed of a hard, grayish, or
yellowish, translucent or opaque matter, which gradually
softens, and excites suppuration in its vicinity. It is
most frequently found in the lungs, causing consumption.
[1913 Webster]
{Tubercle bacillus} (Med.), a minute vegetable organism
({Mycobacterium tuberculosis}, formerly {Bacillus
tuberculosis}, and also called {Koch's bacillus})
discovered by Koch, a German physician, in the sputum of
consumptive patients and in tuberculous tissue. It is the
causative agent of tuberculosis.
[1913 Webster +PJC]