nervous system

American  

[nur-vuhs sis-tuhm] / ˈnɜr vəs ˌsɪs təm /

noun

Anatomy, Zoology.

1. the system of nerves and nerve centers in an animal or human, including the brain, spinal cord, nerves, and ganglia.

2. a particular part of this system.

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nervous system British  

noun

1. the sensory and control apparatus of all multicellular animals above the level of sponges, consisting of a network of nerve cells See neurone See also central nervous system

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nervous system Scientific  

/ nûr′vəs /

1. The system of neurons and tissues that regulates the actions and responses of vertebrates and many invertebrates. The nervous system of vertebrates is a complex information-processing system that consists mainly of the brain, spinal cord, and peripheral and autonomic nerves. It receives chemical information from hormones in the circulating blood and can also regulate secretions of the endocrine system by the action of neurohormones. The nervous systems of invertebrates vary from a simple network of nerves to a complex nerve network under the control of a primitive brain.

2. See also autonomic nervous system central nervous system peripheral nervous system

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nervous system Cultural  

1. The system in the body that controls internal functions of the body and receives, interprets, and responds to stimuli. The nervous system is made up of the brain, the spinal cord, the nerves, and the sense organs, such as the eye and ear.

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Etymology

Origin of nervous system

First recorded in 1730–40

Example Sentences

Chips, cloud computing and AI "are the nervous system of the modern economy", powering everything from defence to healthcare, EU lawmaker Oliver Schenk said.

From Barron's • Jun. 3, 2026

Studies have also shown adverse effects on the nervous system, reproduction, the hormonal system and the functioning of certain organs including the heart, according to ANSES.

From Barron's • Jun. 2, 2026

MS is a disease of the brain and central nervous system, in which the immune system mistakenly attacks the fatty myelin sheath that normally protects the nerves, like insulation around electric wires.

From BBC • May 29, 2026

They then examined how the compound affected immune activity and inflammatory signaling in the central nervous system, which includes the brain and spinal cord.

From Science Daily • May 29, 2026

Stretchers and wheelchairs were beached here and there against the hissing, knocking pipes that ran and branched in an intricate nervous system along the glittering walls.

From "The Bell Jar" by Sylvia Plath