ganglion /gang″glē·on/ pl. ganglia [Gk, knot] , 1. a knot or knotlike mass of nervous tissue. 2. one of the nerve cell bodies, chiefly collected in groups outside the central nervous system. Very small groups abound in association with alimentary organs. The two types of ganglia in the body are the sensory ganglia on the dorsal roots of spinal nerves and on the sensory roots of the trigeminal, facial, glossopharyngeal, and vagus nerves and the autonomic ganglia of the sympathetic and parasympathetic systems.
