Reintegration refers to the process of restoring someone or something back into a group, system, or situation from which they have been removed. It can be used in various contexts such as social reintegration, where an individual who has been incarcerated is helped to readjust and re-enter society; or environmental reintegration, where polluted areas are restored to their natural state through cleanup efforts. In general, the term refers to a return to normalcy after disruption or absence.