What term is used to describe chemical reactions that involve both oxidation and reduction?

The term "redox reactions" is used to describe chemical reactions that involve both oxidation and reduction processes. In such reactions, one species donates electrons (oxidation), while another accepts those electrons (reduction). This electron transfer is fundamental to redox chemistry, as it underlies a wide array of important reactions including combustion, respiration, and corrosion.

During oxidation, there's an increase in the oxidation state of a molecule, whereas during reduction, there's a decrease. The fact that these two processes always occur simultaneously in redox reactions, where electrons are transferred between reactants, distinguishes them from other types of chemical reactions. Other processes, such as synthesis or decomposition reactions, do not inherently involve the concurrent transfer of electrons and, hence, do not fall under the definition of redox reactions.