Battered person syndrome is a physical and psychological condition of a person who has suffered (usually persistent) emotional, physical, or sexual abuse from another person. It is classified as ICD-9 code 995.81 "Battered person syndrome" not elsewhere classified (NEC).
The condition is the basis for the battered spouse defense that has been used in cases of physically and psychologically abused spouses who have killed their abusers. The condition was first researched extensively by Lenore E. Walker, who used Martin Seligman's learned helplessness theory to explain why abused spouses stayed in destructive relationships.