sympathetic nervous system

noun
|Updated on: 22 May 2018

Definition of sympathetic nervous system

: the part of the autonomic nervous system that contains chiefly adrenergic fibers and tends to depress secretion, decrease the tone and contractility of smooth muscle, and increase heart rate — compare parasympathetic nervous system

Recent Examples of sympathetic nervous system from the Web

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First Known Use of sympathetic nervous system

1850

in the meaning defined above

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Medical Dictionary

sympathetic nervous system

noun

medical Definition of sympathetic nervous system

: the part of the autonomic nervous system that is concerned especially with preparing the body to react to situations of stress or emergency, that contains chiefly adrenergic fibers and tends to depress secretion, decrease the tone and contractility of smooth muscle, increase heart rate, and that consists essentially of preganglionic fibers arising in the thoracic and upper lumbar parts of the spinal cord and passing through delicate white rami communicantes to ganglia located in a pair of sympathetic chains situated one on each side of the spinal column or to more peripheral ganglia or ganglionated plexuses and postganglionic fibers passing typically through gray rami communicantes to spinal nerves with which they are distributed to various end organs called also sympathetic system; compare parasympathetic nervous system

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