Definition of parasympathetic in English:



  • Relating to the part of the automatic nervous system that counterbalances the action of the sympathetic nerves. It consists of nerves arising from the brain and the lower end of the spinal cord and supplying the internal organs, blood vessels, and glands.

    ‘The reflexes are mediated by the sympathetic or parasympathetic nerves of the autonomic nervous system, in response to information reaching the central nervous system from a variety of receptors in the organs and tissues.’
    • ‘In autonomic disease, the sympathetic, parasympathetic, and enteric nerves are affected.’
    • ‘Postganglionic parasympathetic nerves mediate both cholinergic contractions and nonadrenergic, noncholinergic relaxations of smooth muscle in the airway.’
    • ‘The toxin also inhibits release of acetylcholine in all parasympathetic and cholinergic postganglionic sympathetic neurones.’
    • ‘So the heart rate is controlled by the balance between the parasympathetic and sympathetic nervous systems' activity.’



/ˌperəˌsimpəˈTHedik/ /ˌpɛrəˌsɪmpəˈθɛdɪk/


Early 20th century from para-‘alongside’ + sympathetic, because some of these nerves run alongside sympathetic nerves.