sympathetic nervous system n.
The part of the autonomic nervous system originating in the thoracic and lumbar regions of the spinal cord that in general inhibits or opposes the physiological effects of the parasympathetic nervous system, as in tending to reduce digestive secretions or speed up the heart.
sympathetic nervous system
The part of the autonomic nervous system that tends to act in opposition to the parasympathetic nervous system, as by speeding up the heartbeat and causing contraction of the blood vessels. It regulates the function of the sweat glands and stimulates the secretion of glucose in the liver. The sympathetic nervous system is activated especially under conditions of stress. Compare parasympathetic nervous system.
noun, Ophthalmology. 1. inflammation of one eye due to injury or disease of the other eye. sympathetic ophthalmia n. A swelling of the uvea in an uninjured eye caused by a wound of the uvea of the other eye. It may eventually lead to bilateral blindness.
noun 1. sympathy strike.
noun 1. a thin wire string, as in various obsolete musical instruments, designed to vibrate sympathetically with the bowed or plucked strings to reinforce the sound.
- Sympathetic trunk
sympathetic trunk n. Either of two long ganglionated nerve strands along the vertebral column that are connected to each spinal nerve by gray matter rami and that receive fibers from the spinal cord through white matter rami connecting with the thoracic and upper lumbar spinal nerves.