"Dr. Frau" is the title of one of my favorite books. It is a memoir of sorts, written by a woman physician named Grace Kaiser. Dr. Kaiser was a country doctor in Lancaster County, PA for 28 years during the 1950's to 70's. I found the book interesting not only because women in medicine in her time were much fewer and farther between than they are now; but also because I am a Pennsylvania native, and thus have a certain fascination with the Amish and Old Order Mennonites who made up the majority of Dr. Kaiser's practice.
They called her "Dr. Frau", which in the "PA Dutch" German dialect means "woman doctor" or "Mrs. Doctor". I adopted that for an email address, and then for a forum name, because I was a middle-aged woman in medical school at the time, and I am of German ancestry. I also thought it would be a joke on myself, since most people think of "Frau" as meaning a disagreeble, battleax, frumpy old woman. (I have had forum names other places like "Harridan" and "Matilda-the-Hun"
Eventually I dropped the "Dr". Since most people weren't familiar with the book, the title seemed to appear presumptuous or something - though if I had called myself "Dr Evil" or "Dr Strangelove", I don't think that would have happened.
So now it's just Frau ( I have no idea why I capitalized it). I've gotten so used to it over the last year that when I applied for a pass to 7 Springs and they asked for a nickname for the back of the pass, I put " Frau".