Slang has been getting a bum rap, accused of cheapening the language, since before the earliest known slang dictionary, the 1699 Dictionary of the Canting Crew, a guide to the street talk of professional rogues. We know the Greeks and Romans used slang. It serves important sociological functions, bonding groups as disparate as bird-watchers, boys at Eton, prisoners, soldiers and (of course) teenagers, while excluding others. "My response to people saying slang destroys the language is: bollocks," says Green. "You always see the same themes: drugs, drink, sex, parts of the body and what people do with them, being nasty to each other, racist stuff. It doesn't do compassion very well. But slang is lively, exciting and very creative."
As raunchy as it can be at times, Urban Dictionary has gone mainstream — I mean, it's even used in some courtrooms to define culturally acceptable slang terms. Doesn't get much more legit than that. Of course, being the crowdsourced slang resource that it is, none of the words were actually invented by Urban Dictionary. However, many (including some of the words below) have since been added to more traditional dictionaries — and others may have been in old-school dictionaries first, but the peeps at Urban Dictionary just defined them better.