respiration

American  

[res-puh-rey-shuhn] / ˌrɛs pəˈreɪ ʃən /

noun

respirations plural

1. the act of respiring; inhalation and exhalation of air; breathing.

2. Biology.

   1. the sum total of the physical and chemical processes in an organism by which oxygen is conveyed to tissues and cells, and the oxidation products, carbon dioxide and water, are given off.

   2. an analogous chemical process, as in muscle cells or in anaerobic bacteria, occurring in the absence of oxygen.

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respiration British  

/ ˌrɛspəˈreɪʃən /

noun

1. the process in living organisms of taking in oxygen from the surroundings and giving out carbon dioxide ( external respiration ). In terrestrial animals this is effected by breathing air

2. the chemical breakdown of complex organic substances, such as carbohydrates and fats, that takes place in the cells and tissues of animals and plants, during which energy is released and carbon dioxide produced ( internal respiration )

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respiration Scientific  

/ rĕs′pə-rā′shən /

1. The process by which organisms exchange gases, especially oxygen and carbon dioxide, with the environment. In air-breathing vertebrates, respiration takes place in the lungs. In fish and many invertebrates, respiration takes place through the gills. Respiration in green plants occurs during photosynthesis.

2. See cellular respiration

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respiration Cultural  

1. The conversion of oxygen by living things into the energy by which they continue life. Respiration is part of metabolism.

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Discover More

Carbon dioxide is a waste product of respiration.

Other Word Forms

Derived Forms

• prerespiration
  noun
• respirational
  adjective

Inflected Forms

Nouns

• respirations
  plural

Etymology

Origin of respiration

1400–50; late Middle English respiracioun < Latin respīrātiōn- (stem of respīrātiō ) a breathing out, equivalent to respīrāt ( us ) (past participle of respīrāre to respire ) + -iōn- -ion

Explanation

Respiration is the act of breathing. You wear a ventilator if you need help with your respiration. Everyone who breathes has the power of respiration. There is, however, another type of respiration which occurs in cells. This is the process of taking in certain substances and putting out others that a cell undergoes to produces energy. One single breath, the inhale and the exhale together, is also called a respiration.

Example Sentences

To investigate, an international team of researchers assembled one of the largest datasets ever used to study soil respiration.

From Science Daily • Jun. 2, 2026

Soil respiration rises, reaches a peak, and then begins to fall.

From Science Daily • Jun. 2, 2026

While convenient, these warmer conditions speed up respiration and ripening, causing fruit to soften and deteriorate more rapidly.

From Science Daily • May 23, 2026

There is no treatment; doctors can offer only supportive care, such as hydration, artificial respiration or dialysis.

From Salon • May 9, 2026

Nearly every cellular function—metabolism, respiration, cell division, self-defense, waste disposal, secretion, signaling, growth, even cellular death—requires proteins.

From "The Gene" by Siddhartha Mukherjee