ganglion
Meaning of ganglion: Ganglion describes both a cluster of nerve cell bodies outside the brain and spinal cord and an unrelated fluid filled cyst near a joint.
Definition of ganglion
A ganglion has two distinct meanings in medicine. In anatomy, a ganglion is a cluster of nerve cell bodies located outside the brain and spinal cord, functioning as a relay point along a nerve pathway. A dorsal root ganglion, for example, contains the cell bodies of sensory nerves carrying information from the body toward the spinal cord, and ganglia are also found throughout the autonomic nervous system.
Separately, a ganglion, often called a ganglion cyst, is a fluid filled sac that develops near a joint or tendon, most commonly on the back of the wrist or hand, connected to the underlying joint capsule or tendon sheath. Despite sharing a name, a ganglion cyst has no connection to nerve tissue.
Because these two meanings describe entirely unrelated structures, one neural and one a soft tissue cyst, the surrounding context makes clear which is intended in a given discussion.
Used in a sentence
A soft, mobile ganglion cyst was noted on examination of the back of the wrist.
Good to know
A ganglion cyst near the wrist and a neural ganglion such as the dorsal root ganglion share only a name, since one is a fluid filled cyst and the other a cluster of nerve cell bodies.
Word origin
Where “ganglion” comes from
Formed from Greek ganglion, originally meaning a swelling or knot beneath the skin, a sense later extended to describe clusters of nerve cell bodies as well.