[TA] the peripheral part of the nervous system external to the brain and spinal cord from their roots to their peripheral terminations. This includes the ganglia, both sensory and autonomic, and any plexuses through which the nerve fibers and all the peripheral nerves run.autonomic (visceral motor) division of nervous system. SYN: pars peripherica systematis nervosi [TA], systema nervosum periphericum*, peripheral part of nervous system.