respiration

noun

res·​pi·​ra·​tion ˌre-spə-ˈrā-shən 

1

a

: the movement of air or dissolved gases into and out of the lungs

b

: a single complete act of breathing

… the patient was cyanotic and unconscious with labored respirations at 40/min.

—Dorwyn W. Croom

2

: the physical and chemical processes (such as breathing and diffusion) by which an organism supplies its cells and tissues with the oxygen needed for metabolism and relieves them of the carbon dioxide formed in energy-producing reactions

3

: cellular respiration

respiratory

ˈre-sp(ə-)rə-ˌtȯr-ē 

ri-ˈspī-rə-

adjective

Examples of respiration in a Sentence

The doctor checked his heartbeat and respiration.

Recent Examples on the Web

Tissue samples from Fern Franco’s remains, obtained by a search warrant, revealed the presence of both morphine, which suppresses respiration, along with the drug succinylcholine, a paralytic used to relax skeletal muscles as during intubation. —Eric Adler, Kansas City Star, 24 Sep. 2025

These microbes react with the air and rock through photosynthesis and respiration to produce organic molecules called metabolites. —Chris Impey, The Conversation, 23 Sep. 2025

The Series 11 accurately measures the duration of your shut-eye, time spent in each sleep stage, other health metrics such as respiration rate and resting heart rate, and even monitors for sleep apnea. —PC Magazine, 16 Sep. 2025

Studies have shown that microplastics can interfere with vital physiological functions in aquatic organisms, affecting respiration, growth, nutrition, reproduction, and survival. —Melissa Cristina Márquez, Forbes.com, 16 Sep. 2025

Word History

Etymology

Middle English respiracioun, from Latin respiration-, respiratio, from respirare

First Known Use

15th century, in the meaning defined at sense 1a

Phrases Containing respiration

• artificial respiration
• cell respiration
• cellular respiration
• external respiration
• internal respiration

Rhymes for respiration

• abdication
• aberration
• abjuration
• abnegation
• abrogation
• acceptation
• acclamation
• acclimation
• accusation
• activation
• actuation
• acylation

Kids Definition

respiration

noun

res·​pi·​ra·​tion ˌres-pə-ˈrā-shən 

1

: the act or process of breathing

2

: the physical processes (as breathing and diffusion) by which a living thing obtains the oxygen it needs to produce energy and eliminate waste gases (as carbon dioxide)

3

: any of various chemical reactions (as oxidation) in cells that release energy from food molecules (as glucose)

Medical Definition

respiration

noun

res·​pi·​ra·​tion ˌres-pə-ˈrā-shən 

1

a

: the movement of respiratory gases (as oxygen and carbon dioxide) into and out of the lungs

b

: a single complete act of breathing

30 respirations per minute

2

: the physical and chemical processes (as breathing and diffusion) by which an organism supplies its cells and tissues with the oxygen needed for metabolism and relieves them of the carbon dioxide formed in energy-producing reactions

3

: cellular respiration