carbon dioxide

See more synonyms for carbon dioxide on
  1. a colorless, odorless, incombustible gas, CO2, present in the atmosphere and formed during respiration, usually obtained from coal, coke, or natural gas by combustion, from carbohydrates by fermentation, by reaction of acid with limestone or other carbonates, or naturally from springs: used extensively in industry as dry ice, or carbon dioxide snow, in carbonated beverages, fire extinguishers, etc.

Origin of carbon dioxide

First recorded in 1870–75
Also called carbonic-acid gas, carbonic anhydride. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for carbon dioxide

Contemporary Examples of carbon dioxide

Historical Examples of carbon dioxide

  • The reduction of the carbon-dioxide would be even more gradual.

  • Then air-rejuvenator apparatus reseparated it from the carbon-dioxide you exhaled, so that you could use it over and over.

    Comet's Burial

    Raymond Zinke Gallun

  • A part is expelled by the lungs as carbon-dioxide, or as it is generally though less correctly termed, carbonic acid.

  • Every molecule of carbon-dioxide that crystallized out took two atoms of oxygen with it, completely out of circulation.

    Let'em Breathe Space

    Lester del Rey

  • In the form of carbon-dioxide the leaves eat up the carbon and oxygen from the atmosphere.

British Dictionary definitions for carbon dioxide

carbon dioxide

  1. a colourless odourless incombustible gas present in the atmosphere and formed during respiration, the decomposition and combustion of organic compounds, and in the reaction of acids with carbonates: used in carbonated drinks, fire extinguishers, and as dry ice for refrigeration. Formula: CO 2Also called: carbonic-acid gas
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for carbon dioxide

1869, so called because it consists of one carbon and two oxygen atoms. The chemical was known since mid-18c. under the name fixed air; later as carbonic acid gas (1791). "The term dioxide for an oxide containing two atoms of oxygen came into use in the middle of the 19th century." [Flood].

Online Etymology Dictionary, © 2010 Douglas Harper

carbon dioxide in Medicine

carbon dioxide

  1. A colorless, odorless, incombustible gas formed during respiration, combustion, and organic decomposition and used in inert atmospheres, fire extinguishers, and aerosols.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

carbon dioxide in Science

carbon dioxide

  1. A colorless, odorless gas that is present in the atmosphere and is formed when any fuel containing carbon is burned. It is breathed out of an animal's lungs during respiration, is produced by the decay of organic matter, and is used by plants in photosynthesis. Carbon dioxide is also used in refrigeration, fire extinguishers, and carbonated drinks. Chemical formula: CO2.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

carbon dioxide in Culture

carbon dioxide

A compound made up of molecules containing one carbon atom and two oxygen atoms.


Carbon dioxide is normally found as a gas that is breathed out by animals and absorbed by green plants. The plants, in turn, return oxygen to the atmosphere. (See carbon cycle and respiration.)


Carbon dioxide is also given off in the burning of fossil fuels (see greenhouse effect).
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.