Relapse
A dictionary definition of relapse may say something like this:- The return of signs and symptoms of a disease after a patient has enjoyed a remission. For example, a patient with cancer went into remission after treatment with no sign or symptom of the tumor, then stayed that way for 3 years, but then suffered a relapse and had to be treated once again for cancer. Relapse could also mean to backslide.
Relapse is not a stage of the cycle of change as such. But it is a significant facet of it. Relapse in addiction means returning to the old behaviour and abandoning the new changes. Sometimes a recovering person may revert to an earlier stage of change. But generally, relapse means going back to pre-contemplation, especially for a recovering drug addict or alcoholic. Smokers may get away more lightly where a relapse may take them back to Contemplation or Preparation.