Definition of ganglion in English:



  • 1Anatomy
    A structure containing a number of nerve cell bodies, typically linked by synapses, and often forming a swelling on a nerve fibre.

    • ‘The two major plexuses consist of ganglia, clusters of nerve cell bodies disposed at more or less regular intervals over the surface of the cylinder.’
    • ‘This nerve carries the otic ganglion, which is derived from glossopharyngeal neurons.’
    • ‘The new regulation expands that prohibition to include dorsal root ganglia, clusters of nerve cells connected to the spinal cord along the vertebrae column.’
    • ‘In the first form (restlessness and dysphagia), the lesions tend to concentrate in the brain stem and the cranial nerve ganglia.’
    • ‘Herpes zoster is caused by reactivation of varicella-zoster virus from a dorsal root ganglion to a cutaneous nerve and the adjacent skin.’
    1. 1.1 A network of cells forming a nerve centre in the nervous system of an invertebrate.
      • ‘If this experiment were possible I would predict that removing the rhopalial ganglion cells would eliminate a behavioral response to light even if the eyes and the swim system remained unharmed.’
      • ‘For some experiments, samples of gill, claw muscle, hepatopancreas, gonad, and thoracic ganglion were also removed to serve as controls.’
      • ‘Swim interneuron isolation was done according to methods previously described by them, by pulling the cell out of the ganglia using the recording microelectrode.’
      • ‘It appears as if all of the staining in the cerebral ganglia is due to processes emanating from cells in the ganglia at the base of the tentacles.’
      • ‘The MIH transcript is detectable in eyestalk neural ganglia throughout the molt cycle of the blue crab, Callinectes sapidus.’
    2. 1.2 A well-defined mass of grey matter within the central nervous system.
      See also basal ganglia
      • ‘Parkinson's disease affects a part of the brain's motor system called the basal ganglia.’
      • ‘It is deposited in those brain ganglia that normally house iron.’
      • ‘In normal circumstances, nerve cells in the part of the brain called the basal ganglia produce the chemical dopamine.’
      • ‘Occurrence of neurodegeneration was indicated by the vacuolar appearance of neural tissues of the brain or ganglia.’
      • ‘Inflammation is commonly present in the basal ganglia, brainstem, spinal cord, and dorsal root ganglia and is composed of a perivascular lymphocytic infiltrate with accompanying glial reaction.’
  • 2Medicine
    An abnormal benign swelling on a tendon sheath.

    • ‘The most commonly considered diagnoses are ganglion, implantation dermoid, cyst, abscess, lipoma, subcutaneous foreign body granuloma, and tendon sheath xanthoma.’
    • ‘Flexor tendon sheath ganglia make up the remaining 10 to 15 percent.’
    • ‘It is the breakdown of the synovial tissue of tendon sheaths that gives rise to most ganglia.’
    • ‘Metastatic lesions may be confused with a ganglion, epidermoid inclusion cyst, acute gout, and even rheumatoid arthritis.’
    • ‘The differential diagnosis of a suture granuloma includes abscess, surgical wound inflammation, lipoma, neoplasm, or ganglion cyst.’


Late 17th century: from Greek ganglion ‘tumour on or near sinews or tendons’, used by Galen to denote the complex nerve centres.