Definition of ganglion in English:


nounganglia, ganglions

  • 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.’
    • ‘In the first form (restlessness and dysphagia), the lesions tend to concentrate in the brain stem and the cranial nerve ganglia.’
    • ‘The new regulation expands that prohibition to include dorsal root ganglia, clusters of nerve cells connected to the spinal cord along the vertebrae column.’
    • ‘Herpes zoster is caused by reactivation of varicella-zoster virus from a dorsal root ganglion to a cutaneous nerve and the adjacent skin.’
    1. 1.1A network of cells forming a nerve centre in the nervous system of an invertebrate.
      • ‘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.’
      • ‘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.’
      • ‘The MIH transcript is detectable in eyestalk neural ganglia throughout the molt cycle of the blue crab, Callinectes sapidus.’
      • ‘For some experiments, samples of gill, claw muscle, hepatopancreas, gonad, and thoracic ganglion were also removed to serve as controls.’
    2. 1.2A well-defined mass of grey matter within the central nervous system.
      See also basal ganglia
      • ‘It is deposited in those brain ganglia that normally house iron.’
      • ‘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.’
      • ‘Parkinson's disease affects a part of the brain's motor system called the basal ganglia.’
      • ‘In normal circumstances, nerve cells in the part of the brain called the basal ganglia produce the chemical dopamine.’
  • 2Medicine
    An abnormal benign swelling on a tendon sheath.

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