Mostly used on online games.
Muling is the process where an experienced player of an online game gives items or money to a new player (most commonly a friend) to help them get started in the virtual environment.
Thus making this new player much better than anyone else who like him has just started.
a.k.a twinking
Friend 1: I'll give you some rareitems and money so you can beat other new players.
Friend 2: Isn't that muling?
Friend 1: So....?
mule
n.
1. A carrier of things for someone else; often used to refer to a carrier of illegal drugs, or a video game character who functions as a holding space for items for another character.
Mulebob is a 1st level character who's a mule for all our gear that we haven't sold yet.
We'll give that item to Mulebob to mule over to your character in that other place.
By Aubry
Mule
The offspring of a mare and a jackass. Useful as a plough animal, and also a fine ride in rugged terrain. These creatures are almost always sterile. They have the coat of a horse and the voice of a donkey.
An acronym used by military officers to describe all the women around them as either: married, ugly, lesbian, or enlisted.
All the women are M.U.L.E.'s around here and it's downright suicide inducing.
By Lurlene
The Mule
A sexual move whereby during doggy style sex the penis, in one swift move, is removed from the vagina and reintroduced into the anus (also known as changing at baker street). The shock causes the recipient's head to rear up at which point the gentleman smacks it down with his fist as one would a miscreant pack animal. Hilarity ensues for all involved. Except possibly for the "mule-ee".