carbon dioxide

/ˌˈkɑrbən daɪˌɑksaɪd/

/ˈkɑbən daɪˈɒksaɪd/

Carbon dioxide is a gas that's formed when fossil fuels are burned. The increasing amount of carbon dioxide in the atmosphere is one of the largest contributors to global warming.

Carbon dioxide, a gas you can't see or smell, is produced when carbon bonds with oxygen. This explains the name: di- means "two," and dioxide refers to two oxygen atoms. This gas occurs naturally, from fermentation and the breathing of animals, and plants rely on atmospheric carbon dioxide to grow. However, by burning oil, gasoline, and coal, humans have produced an excessive amount of this gas, which is trapping heat in our atmosphere and warming the planet.

Definitions of carbon dioxide

1. noun

   a heavy odorless colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis
   synonyms: CO2, carbonic acid gas

   types:

   blackdamp, chokedamp

   the atmosphere in a mine following an explosion; high in carbon dioxide and incapable of supporting life

   type of:

   dioxide

   an oxide containing two atoms of oxygen in the molecule

   greenhouse emission, greenhouse gas

   a substance in the air that warms a planet by trapping heat