tubercle (tōˈbərkyōlˌ) [key] [Lat., = little swelling], small, usually solid, nodule or prominence. In anatomy the term is applied to natural prominences in certain muscles, to nerve nuclei of the central nervous system, and to eminences on bones, especially in regions where muscles (through tendons) or bones (through ligaments) are attached. In dentistry tubercle refers to the cusp of a tooth. In pathology it describes small morbid growths, particularly the lesions of tuberculosis. In botany it applies to the nodules on the roots or leaves of plants. In entomology the term is used for a compound or supplementary eye and for the nodules on the bodies of certain insects.