A website that allows the user to define words. Urban dictionay contains hundreds of thousands of words each submited then if accepted rated with thumbs up or down.
person 1: hey you heard of that website Urban dicationary .com
person 2: yeah
person 1: oh...
Person 2: Now i know what a pean is.
Person 1: what the hell is a pean?
Person 3: oooohhh so thats what an emo is, i always thought it was a type of bird.