1. the condition of being dissociated into ions (as by heat or radiation or chemical reaction or electrical discharge) - the ionization of a gas • Syn: ionization • Derivationally related forms: ionise, ionize (for: ionization) • Hypernyms: condition, status 2. the process of ionizing; the formation of ions by separating atoms or molecules or radicals or by adding or subtracting electrons from atoms by strong electric fields in a gas • Syn: ionization • Derivationally related forms: ionise, ionize (for: ionization) • Hypernyms: natural process, natural action, action, activity