respiratory system

American  

noun

Anatomy.

• respiratory systems
  plural

1. the system by which oxygen is taken into the body and an exchange of oxygen and carbon dioxide takes place; in mammals the system includes the nasal passages, pharynx, trachea, bronchi, and lungs.

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respiratory system British  

noun

1. the specialized organs, collectively, concerned with external respiration: in humans and other mammals it includes the trachea, bronchi, bronchioles, lungs, and diaphragm

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respiratory system Scientific  

1. The system of organs and structures in which gas exchange takes place, consisting of the lungs and airways in air-breathing vertebrates, gills in fish and many invertebrates, the outer covering of the body in worms, and specialized air ducts in insects.

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respiratory system Cultural  

1. The organs in the body involved in respiration. Air enters the body through the nose and mouth and travels down the trachea, through the bronchial tubes, and finally into the lungs. Once in the lungs, the air is drawn into an enormous number of thin-walled sacs richly supplied with capillaries. The exchange of oxygen and carbon dioxide in the blood takes place in these tiny sacs.

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Other Word Forms

Noun Inflected Forms

• respiratory systems
  plural

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Etymology

Origin of respiratory system

First recorded in 1935–40

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Example Sentences

See Examples For:

respiratory system

These features indicate that Montsecosuchus already possessed an efficient respiratory system that shared certain similarities with those of modern crocodiles.

From Science Daily ● Sep. 15, 2026

The colorless gas can harm the respiratory system of sensitive individuals, according to the Environmental Protection Agency.

From The Wall Street Journal ● May 21, 2026

It’s one of the nation’s largest sources of sulfur dioxide, which forms haze and harms the respiratory system, and the second-largest source of carbon dioxide, according to EPA data.

From Salon ● May 10, 2026

The provincial livestock office in Chiang Mai said in a statement on Friday that testing detected the highly infectious canine distemper virus as well as bacteria affecting the respiratory system.

From Barron's ● Feb. 21, 2026

How much oxygen does a person’s respiratory system exchange for carbon dioxide every hour?

From "All the Light We Cannot See" by Anthony Doerr

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