Being a survivor means taking a transition from sexual assault or abuse 'victim' to someone who appreciates how they endured the pain of sexual abuse or rape.
Survivors appreciate what they had to do to get themselves through the abuse or the assault. They have now taken control of their bodies and healing. One can acknowledge oneself as surviving the trauma from an assault of a forced sexual nature, whether it happened once or occured ritualistically for a long period of time which left a psychological, emotional and physical aftermath that must be addressed and processed.
People of any age, origin or gender that experience sexual assault, child abuse, rape, incest or any sexual act against their will are commonly known as victims, forced into the victim category which has connotations of fragility and naivety. The term survivor connotes an act of renaming which is a catalyst to aid in healing, moving forward and regaining control.
Being a survivor is acknowledging how you have suffered and taking an active role in your healing journey.
http://rapesurvivor.pbwiki.com/survivor has definitions from survivors on how they define themselves, the book Quest for Respect describes in more detail the process of transitioning from the victim to the survivor stage of healing.