A specific act involving a midget, a woman, and a 100-foot slide-and-slide. The woman lays back at the end of the slip-and-slide with her legs wide open. The midget then is slid down the slip-and-slide at a high speed, resulting in the midget sliding all the way down the slip-and-slide, and going so far into the woman's vagina that it ends up entirely inside of her, resulting in what looks like a birth in reverse (hence the name, reverse birthing).
A hardo is a person who tries extremely hard at everything. Most times a hardo will try very hard at things that do not require excessive effort. For example, sports practices, gym class, etc.
Wow did you see Jack at practice today? What a hardo!