ganglion

Etymology

Borrowed from Ancient Greek γᾰγγλῐ́ον (ganglíon, “encysted tumour on a tendon or aponeurosis”).

noun

1. (neuroanatomy)
   1. An encapsulated collection of nerve cell bodies, typically linked by synapses, and often forming a swelling on a nerve fiber.
   2. Any of certain masses of gray matter in the central nervous system, as the basal ganglia.
      The yawning gap in neuroscientists’ understanding of their topic is in the intermediate scale of the brain’s anatomy. Science has a passable knowledge of how individual nerve cells, known as neurons, work. It also knows which visible lobes and ganglia of the brain do what. But how the neurons are organised in these lobes and ganglia remains obscure. 2013-08-03, “The machine of a new soul”, in The Economist, volume 408, number 8847
2. (transferred sense) A centre of intellectual or industrial force, activity, etc.
3. (pathology) A benign cystic tumour on a tendon sheath or joint capsule.