nervous system

American  

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

noun

Anatomy, Zoology.

• nervous systems
  plural

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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Other Word Forms

Noun Inflected Forms

• nervous systems
  plural

Etymology

Origin of nervous system

First recorded in 1730–40

Example Sentences

See Examples For:

nervous system

As development progresses, their descendants gradually become more specialized, eventually forming structures such as the nervous system, skin, blood, and eyes.

From Science Daily ● Oct. 13, 2026

The Middle East is, among other things, like a cerebrum of the world nervous system: its exposed nerves—trade routes and oil pipelines—making it especially sensitive to the rest of the body.

From The Wall Street Journal ● Oct. 4, 2026

Christa Pike, 50, on Wednesday survived two lethal injections of pentobarbital, a drug that suppresses nervous system activity.

From Barron's ● Oct. 4, 2026

Lopez’s medical bills are covered by workers’ compensation insurance, but her health has worsened and her doctor has referred her to specialists who deal with respiratory and nervous system disorders, she said.

From Los Angeles Times ● Sep. 24, 2026

Both major types of insecticides, the chlorinated hydrocarbons and the organic phosphates, directly affect the nervous system, although in somewhat different ways.

From "Silent Spring" by Rachel Carson