Characteristics of posttraumatic stress disorder (PTSD) may be influenced by newly experienced traumata or confrontation with trauma-associated stimuli. Terms like reactivation or retraumatization are used either to describe slightly, temporary or severe and permanent increase in PTSD symptoms. Trigger, duration and intensity of a potential increase in symptoms have not been consistently defined yet. The purpose of this overview is to operationalize the term retraumatization on the background of empirical studies and to deduce a standardized definition. Furthermore implications for research and clinical practice are discussed.