Answer: decondition

AnswerCrossword Clue
deconditionReform or reverse (previously conditioned behavior), esp. in the treatment of phobia and other anxiety disorders in which the fear response to certain stimuli is brought under control
deconditionto cause extinction of (a conditioned response)
deconditionPersuade (someone) to abandon a habitual mode of thinking
deconditionCause to lose fitness or muscle tone, esp. through lack of exercise