What does oxide mean?
An oxide is a chemical compound formed when oxygen is combined with another element. The term covers many familiar materials, including metal oxides such as iron oxide, the principal component of rust, and aluminium oxide, which is used in abrasives and ceramics. Oxides can have markedly different properties: some are chemically stable and protective, while others react readily with acids, water, or other substances. In metallurgy, an oxide layer may form on a metal’s surface and either protect it or contribute to its deterioration. The word is also central to naming conventions in which the oxygen content of a compound is indicated with the ending “-oxide,” as in carbon dioxide. Although an oxide is a substance, oxidation is the process that may produce it. Both concepts are important in chemistry, environmental science, metallurgy, and the study of materials.
nounA chemical compound composed of oxygen and one or more other elements. In the strict sense, an oxide is a binary compound in which oxygen is combined with another element.
- A chemical compound of oxygen with another element.
"A thin layer of oxide forms on the surface of the metal when it is heated in air."
"The coating protects the steel beneath it from further oxidation."
"The mineral was identified as a form of iron oxide."
The plural is used when referring to several distinct oxygen compounds or classes of oxygen compounds.
"Several metallic oxides are used as catalysts in industrial reactions."
Oxides helped chemists turn oxygen from an atmospheric gas into a building block of matter—and produced materials as familiar as rust and glass.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does oxide come from?
The word oxide entered English from French in the late eighteenth century as part of the developing terminology of chemistry. Its formation combines an oxy- element, ultimately associated with Greek oxys, meaning “sharp” or “acidic,” with the chemical suffix -ide. This etymological connection reflects the historical role of oxygen in defining acids and gave rise to a wider family of scientific words.
Related word forms
How oxide is actually used
The term is primarily used in chemistry and materials science. Its meaning can be broad, as in a metal oxide, or more specific, as when it denotes a binary oxygen compound.
Easily confused with oxide
An oxide is a compound containing oxygen, whereas oxidation is the chemical process in which a substance gains oxygen or undergoes an increase in its oxidation state.