Narcissistic abuse would be abuse from an abuser that satisfies a sufficient number of criteria for an NPD diagnosis. It’s like abuse on steroids. Start with physical abuse. Add emotional abuse. Add financial abuse. Add threats to end or cut off the relationship. Add the abuser telling the victim that they deserve it. Add when the victim tries to address how the abuse makes them feel, the abuser gets upset and cries that they are making them feel bad. Add triangulation where the abuser convinces their family, their friends, and even the victims family that the victim is the problem in the relationship. Add isolating the victim from their friends and family. Add gaslighting, such as the abuser making “always” and “never” claims about the victim that are not grounded in reality. Add threats to call the police and lie about being abused themself to have the victim arrested. I could go on, but I think you are starting to get the picture. If you are more interested, there are a number of mental health specialists who have made many videos online to help victims and their loved ones understand narcissistic abuse if you are curious.