General English


  • noun a colourless, odourless gas, essential to human life, constituting 21 per cent by volume of the Earth’s atmosphere

Cars & Driving

  • noun a gaseous element essential for life and the combustion of fuel.


  • A chemical element that is a colorless, odorless, and tasteless diatomic gas whose atomic number is 8. It comprises about 21% of the atmosphere, nearly 50% of the earth's crust, and almost 90% of water, making it the most abundant element on the planet. It is very reactive, forming compounds with almost every element, and has over one dozen known isotopes, of which 3 are stable. Its applications include its use in most combustion reactions, such as those occurring during the utilization of most fuels. Its chemical symbol is O.
  • chemical symbolO


  • The gas which is necessary for most animal life and which forms about 20 per cent of the air. At high temperatures it causes oxidation and deterioration of food. The rate of oxidation doubles for every 10°C increase in temperature. Occasionally used as a packaging gas.


  • noun a chemical element that is a common colourless gas which is present in the air and essential to human life


  • a chemical element (formula O) that is a common colourless gas present in the air and essential to biological life. In winemaking it is important to exclude oxygen from most processes because of the risk of oxidation. Exposure to the air before drinking is sometimes thought to improve some red wines.

Origin & History of “oxygen”

Etymologically, oxygen means ‘acid-former’. The word was coined in French in the late 1780s as oxygène, based on Greek oxús ‘sharp, acid’ (a descendant of the same Indo-European base, *ak- ‘be pointed’, as produced English acid, acute, etc) and the Greek suffix-genes, denoting ‘formation, creation’ (a descendant of the Indo-European base *gen- ‘produce’, which has given English a vast range of words, from gene to genocide).