dioxide
Chemistry term used as a noun or prefix to indicate a compound with two oxygen atoms, e.g., 二酸化炭素 (carbon dioxide).
二酸化炭素は温室効果ガスの一つです。
Carbon dioxide is one of the greenhouse gases.
二酸化硫黄は火山ガスに含まれています。
Sulfur dioxide is contained in volcanic gases.
Means 'oxidation' or 'oxide' in general; 二酸化 specifies two oxygen atoms.
carbon dioxide; CO2
lead dioxide; lead(IV) oxide
chlorine dioxide
sulfur dioxide; sulphur dioxide
nitrogen dioxide
Compound of 二 (two) + 酸化 (oxidation), literally 'two-oxidation', a straightforward chemical naming pattern.
manganese dioxide (MnO2)
carbon dioxide fixation
carbon emission right; right to emit carbon dioxide