Real Dictionary

carbon dioxide
uncountable noun: Carbon dioxide is a gas. It is produced by animals and people breathing out, and by chemical reactions.

carbon dioxide in American English
a colorless, odorless, incombustible gas, CO2, somewhat heavier than air, that is a product of respiration and combustion: produced commercially and used widely in fire extinguishers, carbonated beverages, etc.: in photosynthesis, carbon dioxide and water
noun: 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 carbona

carbon dioxide in British English
noun: 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 dr

carbon dioxide in the Pharmaceutical Industry
noun: Carbon dioxide is a colorless, odorless gas formed during respiration, the decomposition and combustion of organic compounds, and in the reaction of acids with carbonates.