dioxide
n. C / U B2 Upper Intermediate US //daɪˈɑkˌsaɪd// UK //daɪˈɒksaɪd// diox·ide
n. a chemical substance that has two oxygen atoms for every one atom of another element. You most often hear about it when people talk about the air or the environment.
n. an oxide containing two atoms of oxygen in each molecule. Frequently used in compound nouns to specify the non-oxygen element.
Plants absorb carbon dioxide from the air to grow.
The factory installed new filters to reduce the amount of sulfur dioxide released into the atmosphere.
While carbon dioxide is essential for photosynthesis, its increasing concentration in the atmosphere is a primary driver of the greenhouse effect and global climate change.
From di- + oxide.