sympathetic trunk, one of a pair of chains of ganglia extending along the side of the vertebral column from the base of the skull to the coccyx. Each trunk is part of the sympathetic nervous system and consists of a series of ganglia connected by various types of fibers. Each sympathetic trunk distributes branches with postganglionic fibers to the autonomic plexuses, the cranial nerves, the individual organs, the nerves accompanying arteries, and the spinal nerves.
