autonomic nervous system

American  

noun

1. the system of nerves and ganglia that innervates the blood vessels, heart, smooth muscles, viscera, and glands and controls their involuntary functions, consisting of sympathetic and parasympathetic portions.

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autonomic nervous system British  

noun

1. the section of the nervous system of vertebrates that controls the involuntary actions of the smooth muscles, heart, and glands. It has two divisions: the sympathetic and the parasympathetic Compare somatic nervous system

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autonomic nervous system Scientific  

/ ô′tə-nŏm′ĭk /

1. The part of the vertebrate nervous system that regulates involuntary activity in the body by transmitting motor impulses to cardiac muscle, smooth muscle, and the glands. The muscular activity of the heart and of the circulatory, digestive, respiratory, and urogenital systems is controlled by the autonomic nervous system. The autonomic nervous system is divided into two parts: the sympathetic nervous system and the parasympathetic nervous system.

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autonomic nervous system Cultural  

1. The part of the nervous system that controls involuntary functions of the body (those not controlled consciously), such as digestion, the beating of the heart, and the operation of glands in the endocrine system.

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Etymology

Origin of autonomic nervous system

First recorded in 1895–1900

Example Sentences

The 44-year-old Los Angeles resident says the peptides have helped with myriad symptoms she has long struggled with due to a disorder of her autonomic nervous system.

From The Wall Street Journal • Apr. 20, 2026

When you see green trees, smell pine and hear gentle rustling leaves or the sound of birdsong, your autonomic nervous system - a network of nerves controlling unconscious processes - responds instantly.

From BBC • Oct. 9, 2025

Your autonomic nervous system regulates heartbeat and blood pressure, but with POTS, the body stops keeping these functions in check, causing symptoms like nausea, dizziness, and extreme fatigue.

From Slate • Sep. 15, 2025

"Our future research will search for ways to block these complications and protect the adrenal gland from receiving 'false' autonomic nervous system information originating from the spinal cord below the lesion site."

From Science Daily • Dec. 21, 2023

“The android autonomic nervous system isn’t as flexible at cutting in and out as ours. But as you say, this wouldn’t work for more than five or six seconds.”

From "Do Androids Dream of Electric Sheep?" by Philip K. Dick