Definition of “oxygen” - English Dictionary

british dictionary

“oxygen” in British English

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oxygennoun [ U ]

uk /ˈɒk.sɪ.dʒən/ us /ˈɑːk.sɪ.dʒən/ symbol O

B2 a chemical element that is a gas with no smell or colour. Oxygen forms a large part of the air on earth, and is needed by animals and plants to live.

Examples

  • Air is composed mainly of nitrogen and oxygen.
  • Deep-sea divers carry cylinders of oxygen on their backs.
  • Mountain climbers use oxygen when they reach higher altitudes.
  • Plants are the main source of atmospheric oxygen.
  • The symbol for oxygen is O2.

Examples from literature

  • Blood carries oxygen through the body. 
  • Broken bones, organ damage, shock, lack of oxygen, and extreme cold all reduce your chances of survival. 
  • Laughing is good for your brain and your heart because they need a lot of oxygen to work well. 
  • Space is almost a vacuum, with neither the pressure nor oxygen to support the human body. 
  • The oxygen problem was finally solved by the use of pressurized cabins, allowing balloons to rise higher and higher. 
  • The problems at such a high altitude are the cold, low air pressure, and lack of oxygen. 
  • Their roots are above the water and can “breathe” oxygen. 
  • To save oxygen and energy, stay calm. 
  • Water is made up of two chemicals, hydrogen and oxygen. 

(Definition of “oxygen” from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)

“oxygen” in American English

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oxygennoun [ U ]

us /ˈɑk·sɪ·dʒən/

biology, chemistry a colorless gas, one of the chemical elements, that forms a large part of the air on earth and is needed to keep most living things alive and to create fire

(Definition of “oxygen” from the Cambridge Academic Content Dictionary © Cambridge University Press)