Loosely defined, it's a person relating to the abuser is a hero, due to a distorted idea of the identity of that abuser, because of mind control tactics and manipulation and crafty cooercion used by said abuser, in order to appear as benevolent, rather than sinister and dangerous.
Now, I want to say this. I have run into this phenomena in people I have counseled and ministered to. It is both understandable and infuriating to me.
I can't begin to tell you the mixture of compassion and frustration I feel when I hear an abused adult actually DEFEND a mother who lays a "guilt trip" on them as to why they didn't call them every day, adore the gift they gave them and use it in every single room of the house, or just basically devote every waking moment to hearing about all their aches and pains and woes that are nothing more than bids for selfish attention.
When I watch an adult go running over to "mommy's" house, because "if I don't, she'll be mad..." at 40 somethin years old, I'm filled with a mixture of feelings...pity and compassion on the adult-child who never individuated healthfully from her mother, anger at a mother who continues to USE and MANIPULATE a grown adult, and frustration at a family who lived and hid a lie for years and a society who didn't step in and stop it and still doesn't bother to. I see this over and over again...families walking on eggshells and then a person like me, goes and stays in the home, notices the things that aren't right, the control tactics over the children, etc, yet, when we go to report it, there is such deep family denial and support of the abuser, that nothing is ever done to help...that abuser grows up to have children who grow up to have children and the cycle continues, and NOBODY SHOUTS "the EMPORER IS NAKED!"