oxide
n.a chemical substance that forms when oxygen combines with another element. You might know it as rust when it happens to iron.
n.a binary compound of oxygen with another element or group. Often used in technical contexts to describe the result of oxidation processes.
“Iron oxide is the scientific name for rust.”
“The chemist analyzed the white powder and identified it as zinc oxide, commonly used in sunscreens.”
“Environmental regulations have become increasingly strict regarding the emission of nitrogen oxide from industrial plants due to its role in the formation of acid rain.”
Uncountable when referring to the chemical substance in general; countable when referring to specific types or varieties of the compound.
“The analysis showed that the red pigment in the paint appeared to come from local red clay, which contains microscopic iron oxide particles (nano-hematite).”
“Researchers at the University of Surrey found that sodium vanadium oxide performs much better when its naturally occurring water is left inside instead of being removed during manufacturing.”
Common in science and technology writing
Archaic French oxide (now oxyde), from a blend of ox(ygene) and (ac)ide, coined by G. de Morveau and A. Lavoisier. By surface analysis, ox- + -ide.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.