Richard Pryor's Daughter Claims Her White Mother Called Her the N-Word During Argument

Richard Pryor's daughter is opening up life as a kid of the legendary funnyman ... and one memory in particular is pretty messed up ... and it involves her mother, a fight, and a racial slur.

Elizabeth Stordeur Pryor, Richard's third eldest child with Maxine Silverman, says in her new book, "Something We Said: Richard Pryor, a Notorious Word, and Me" that her white mom called her the N-word during an argument when she was just 12 years old.

That memory is seared into her mind ... and she says it was one of her earliest traumatic experiences as a biracial woman.

Elizabeth told PEOPLE she knew her mother loved her ... but she also says she never discussed being Black with her mother's side of the family.

But Elizabeth says ignoring her background only led to questions ... she says she asked her cousins, "Did you know that I was Black?" and ... "Were you told to behave in a particular way around it?''