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Related to nodule: Thyroid nodule


a small node that is solid and can be detected by touch.
Albini's n's gray nodules of the size of small grains, sometimes seen on the free edges of the atrioventricular valves of infants; they are remains of fetal structures.
apple jelly n's minute, yellowish or reddish brown, translucent nodules, seen on diascopic examination of the lesions of lupus vulgaris.
Aschoff's n's Aschoff's bodies.
Gamna n's brown or yellow pigmented nodules seen in the spleen in certain cases of enlargement, such as Gamna's disease and siderotic splenomegaly.
Jeanselme's n's (juxta-articular n's) gummata of tertiary syphilis and of nonvenereal treponemal diseases, located on joint capsules, bursae, or tendon sheaths.
lymphatic nodule
2. a small dense accumulation of lymphocytes found within the cortex of a lymph node, expressing the cytogenic and defense functions of the tissue. Called also lymph or lymphatic follicle.
milker's n's hard circumscribed nodules on the hands of those who milk cows affected with cowpox.
rheumatic n's small, round or oval, mostly subcutaneous nodules made up chiefly of a mass of Aschoff's bodies and seen in rheumatic fever.
Schmorl's nodule Schmorl's node.
singer's n's vocal cord nodules.
surfer's n's hyperplastic, fibrosing granulomas occurring over bony prominences of the lower limbs and feet as a result of repeated trauma from kneeling on surfboards.
teacher's n's vocal cord nodules.
typhus n's minute nodules produced by perivascular infiltration of polymorphonuclear leukocytes and mononuclear cells in rickettsial disease; they were originally described in typhus.
nodule of vermis the part of the vermis of the cerebellum, on the ventral surface, where the inferior medullary velum attaches.
vocal n's (vocal cord n's) small white nodules appearing on the vocal cords in chorditis tuberosa with excessive use of the voice; called also singer's nodes or nodules and teacher's nodes or nodules.


(nod'yūl), [TA]
A small node; in skin, a node up to 1.0 cm in diameter, solid, with palpable depth; a pulmonary or pleural lesion seen on a radiographic image as a well-defined, discrete, roughly circular opacity 2-30 mm in diameter. Compare: mass.
Synonym(s): nodulus (1) [TA]
[L. nodulus, dim. of nodus, knot]


1. A small knotlike protuberance.
2. Medicine A small, abnormal but usually benign mass of tissue, as on the thyroid gland, in the lung, or under the skin.
3. Botany A small knoblike outgrowth, especially one on the roots of a leguminous plant that contains bacteria that fix nitrogen.
4. Mineralogy A small rounded lump of a mineral or mixture of minerals, usually harder than the surrounding rock or sediment.

nod′u·lar (nŏj′ə-lər), nod′u·lose′ (-lōs′)(-ləs), nod′u·lous (-ləs) adj.


The most commonly used medical term for a small node, bump, swelling, or protuberance.


A small node, bump, swelling, protuberance. See Apple jelly nodule, Cold nodule, Hot nodule, Pseudorheumatoid nodule, Renal nodule, Rheumatoid nodule, Satellite nodule, Sister Mary Joseph nodule, Solitary thyroid nodule, Surfer's nodule, Tobacco nodule, Typhoid nodule, Warm nodule.


(nod'yūl) [TA]
A small node.
Synonym(s): nodulus (1) .
[L. nodulus, dim. of nodus, knot]


(noj'ool?) [L. nodulus, little knot]
1. A small node.
2. A small cluster of cells.

aggregate nodules

A group of unencapsulated lymph nodules, such as Peyer's patches of the small intestine.

Albini's nodules

See: Albini's nodules

apple jelly nodule

The jelly-like lesion of lupus vulgaris.

Arantius' nodule

See: Arantius, Julius Caesar

Aschoff's nodules

See: Aschoff's nodules

Bracht-Wachter nodules

Bracht-Wachter bodies.

cortical nodules

Lymph nodules located in the cortex of a lymph node.

laryngeal nodule

Singer's node.

lymph nodule

A mass of compact, densely staining lymphocytes forming the structural unit of lymphatic tissue. These nodules may occur singly, in groups (as in Peyer's patches), or in encapsulated organs such as lymph nodes. Each contains a lighter-staining germinal center where new lymphocytes are formed.

miliary nodule

Small round density, 1 to 5 mm in diameter, as seen on the chest radiograph (e.g., in disseminated tuberculosis).

milker's nodules

Painless smooth or warty lesions due to a poxvirus that is transmitted from the udders of infected cows to the hands of milkers.
See: paravaccinia

rheumatic nodules

Subcutaneous nodes of fibrous tissue that may be present in patients with rheumatic fever.
See: subcutaneous nodule for illus.

Schmorl's nodule

Schmorl's node.

nodule of the semilunar valve

Arantius' body.

siderotic nodules

Small brown nodules seen in the spleen and other organs and consisting of necrotic tissue encrusted by iron salts.

solitary nodule

An isolated nodule of lymphatic tissue such as occurs in mucous membranes.

solitary pulmonary nodule

Any isolated mass lesion found in the lung, usually during an x-ray study performed for another reason. Most small masses that are identified in this way are benign, although smokers, patients already known to have cancer in another organ system, and older patients have an increased risk that a solitary nodule will be a new malignancy or a metastasis from another source.

Patient care

The first step in evaluating a solitary lung nodule is to search for prior chest x-ray films. If the nodule can be found on films done many months or years earlier and has not changed in size, shape, or calcification, it is likely to be benign and can be followed conservatively. Newly identified lesions within the lung that were not previously present usually are evaluated with further studies, such as computed tomography of the lungs, sputum studies, or biopsies.

Enlarge picture

subcutaneous nodules

Small, nontender swellings resembling Aschoff's bodies and found over bony prominences in persons with rheumatic fever or rheumatoid arthritis (in rheumatoid arthritis, they are called rheumatoid nodules).
See: illustration
Enlarge picture

surfer's nodules

Nodular swelling and possible bone changes of the area of the lower leg and foot exposed to pressure and trauma while on a surfboard. The nodules may be painful.
Synonym: surfer's knots See: illustration

thyroid nodule

A visible or palpable mass in the thyroid gland, benign about 90% to 95% of the time. A history of radiation to the head or neck increases the likelihood that the lesion will be malignant, as does the appearance of the nodule in the first decades of life. Fine-needle aspiration biopsy is the first and often the definitive diagnostic test.

typhoid nodules

Nodules characteristic of typhoid fever and found in the liver.

typhus nodules

Small nodules of the skin seen in typhus. They are composed of mononuclear cell infiltration around vessels.


A small, solid knot-like lump of tissue occurring anywhere in the body. Nodules in the skin are easily felt. The term implies nothing about the nature of the lump.


  1. any small spherical swelling.
  2. short for root nodule. (see NITROGEN FIXATION).


A swelling or knob that may form on a tendon and make it difficult to slide smoothly through its sheath.
Mentioned in: Mycetoma, Trigger Finger


A small, circumscribed mass of tissue or an aggregation of cells.
Busacca's nodule's Nodules often found in the iris stroma of an eye affected by granulomatous uveitis (up to about 30% of cases). Syn. floccules of Busacca. See iris nodules.
Dalen-Fuchs nodule's Multiple, small yellow-white mounds consisting mainly of epithelial cells protruding through the retinal pigment epithelium. They are seen in the fundus of an eye with sympathetic ophthalmia, Vogt-Koyanagi-Harada syndrome or some other granulomatous inflammations.
iris nodule's Small, solid elevations found on the iris and epithelial cells and lymphocytes. They are usually whitish or grey, depending on their location. See Busacca's nodules; Koeppe's nodules; Lisch nodule.
Koeppe's nodule's Small nodules frequently found on the iris around the pupillary margin of an eye affected by granulomatous uveitis. See iris nodules.
Lisch nodule A small, abnormal, lightly pigmented swelling which develops on the surface of the iris in almost all patients with neurofibromatosis type 1 during the second or third decades of life. See von Recklinghausen's disease.


1. A small node; in skin, a node up to 1.0 cm in diameter, solid, with palpable depth.
2. A pulmonary or pleural lesion seen on a radiographic image as a well-defined, discrete, roughly circular opacity.
[L. nodulus, dim. of nodus, knot]
References in periodicals archive ?
After obtaining lung parenchyma 3D image sequences, we need to detect suspected pulmonary nodules. Shape-based selective filtering has been extensively employed in pulmonary nodule detection system.
The initial mode of presentation is usually as solitary thyroid nodule. Lymphatic spread was common with papillary thyroid carcinoma.
Primary Retroperitoneal Mucinous Cystadenoma with a Sarcoma-Like Mural Nodule: An Immunohistochemical Study With Histogenetic Considerations and Literature Review.
The project, called 'Laser and Ultrasound Co-analyser for thyroid nodules' (LUCA), aims to develop a technology that improves data acquisition for medical professionals by probing chemical constitution, water concentration, structure and haemodynamics--like blood flow and oxygenation--of tissue simultaneously.
Given our patient's left nodule was predominantly cystic in nature, it perhaps comes as no surprise that the FNA could only yield "cyst fluid." This form of aspirate falls under the "nondiagnostic" category of the Bethesda system, and metaanalysis actually suggests that up to 16.8% of such nodules are malignant [10].
Caption: Figure 2: Peripheral regular no-enhancement ring of thyroid nodule on CEUS.
Among these 29 patients, the nodule was visualized at fluoroscopy in eight patients and at EBUS miniprobe in 19 patients.
Ultrasound-guided FNAC was performed by surgeon in all cases of solitary thyroid nodule in the Department of Radiology.
In the study, researchers evaluated records for all patients whose thyroid nodules were indeterminate for cancer based on cytopathology and who subsequently underwent molecular testing with the Afirma GSC or the original Afirma Gene Expression Classifier between February 2011 and December 2018.
In conclusion, the presentation of solid and hollow pulmonary nodules, normally highly suspicious of metastases cancer, may be induced by rheumatoid arthritis and may be resolved by treatment with an IL-6 inhibitor (3).
After delineating visible lung region from posterior and anterior chest radiographs, the next step is detecting potential nodule from the segmented image.