autonomic nervous system

noun

: a part of the vertebrate nervous system that innervates smooth and cardiac muscle and glandular tissues and governs involuntary actions (such as secretion and peristalsis) and that consists of the sympathetic nervous system and the parasympathetic nervous system

Examples of autonomic nervous system in a Sentence

Recent Examples on the Web

Higher Bedroom Temperatures Linked to Higher Heart Rates After collecting 14,179 hours of data, the researchers found that those who slept in warmer rooms—above 75 degrees—had higher heart rates and lower HRV, suggesting the autonomic nervous system may be under stress rather than in repair mode. —Julia Ries Wexler, Health, 12 Mar. 2026

The autonomic nervous system shifts from a state of calm engagement to one of defensive mobilization. —Amy Cuddy, New York Times, 18 Feb. 2026

But availability remains a persistent question for Porzingis, who has been limited to 17 games this season, due in part to the chronic autonomic nervous system illness POTS, or postural orthostatic tachycardia syndrome. —Peter Sblendorio, New York Daily News, 5 Feb. 2026

When the autonomic nervous system is not activated, emotionally secure people reduce the perception of threat, both in themselves and in the person across from them. —Mark Travers, Forbes.com, 24 Jan. 2026

Word History

First Known Use

1898, in the meaning defined above

Rhymes for autonomic nervous system

• cryptosystem
• ecosystem
• intersystem
• multisystem
• photosystem
• subsystem

Kids Definition

autonomic nervous system

noun

: the part of the vertebrate nervous system that controls involuntary actions (as heart rate and breathing) and that is made up of the sympathetic nervous system and parasympathetic nervous system

Medical Definition

autonomic nervous system

noun

: a part of the vertebrate nervous system that innervates smooth and cardiac muscle and glandular tissues and governs involuntary actions (as secretion, vasoconstriction, or peristalsis) and that consists of the sympathetic nervous system and the parasympathetic nervous system

called also vegetative nervous system

compare central nervous system, peripheral nervous system