sometimes used as another word for butt, but also used as a name. Fannies are wonderful people who are really really pretty and nice and talented and make the best cousins in the world. Everybody loves them and wishes they were a Fannie!
Basically the most awesome people in the entire world.
Person 1: "Hey, did you know that it't Fannie's birthday on thursday?"
Person 2: "No way! Fannie's the best!! I wish I was her. I hope she has the best one yet"