PITTSBURGH -- Dude, you've got to read this. A linguist from the University of Pittsburgh has published a scholarly paper deconstructing and deciphering the word "dude," contending it is much more than a catchall for lazy, inarticulate surfers, skaters, slackers and teenagers.

An admitted dude-user during his college years, Scott Kiesling said the four-letter word has many uses: in greetings ("What's up, dude?"); as an exclamation ("Whoa, Dude!"); commiseration ("Dude, I'm so sorry."); to one-up someone ("That's so lame, dude."); as well as agreement, surprise and disgust ("Dude.").

Kiesling says in the fall edition of American Speech that the word derives its power from something he calls cool solidarity -- an effortless kinship that's not too intimate.

Cool solidarity is especially important to young men who are under social pressure to be close with other young men, but not enough to be suspected as gay.

In other words: Close, dude, but not that close.

"It's like man or buddy, there is often this male-male addressed term that says, 'I'm your friend but not much more than your friend,"' said Kiesling, whose research focuses on language and masculinity.

To decode the word's meaning, Kiesling listened to conversations with fraternity members he taped in 1993. He also had undergraduate students in sociolinguistics classes in 2001 and 2002 write down the first 20 times they heard "dude" and who said it during a three-day period.

He found the word taps into nonconformity and a new American image of leisurely success.

Anecdotally, men were the predominant users of the word, but women sometimes call each other dudes.

Less frequently, men will call women dudes and vice versa. But that comes with some rules, according to self-reporting from students in a 2002 language and gender class included in the paper.

"Men report that they use dude with women with whom they are close friends, but not with women with whom they are intimate," according to the study.

His students also reported that they were least likely to use the word with parents, bosses and professors.

Historically, dude originally meant "old rags" -- a "dudesman" was a scarecrow. In the late 1800s, a "dude" was akin to a "dandy," a meticulously dressed man, especially out West. It became "cool" in the 1930s and 1940s, according to Kiesling. Dude began its rise in the teenage lexicon with the 1981 movie "Fast Times at Ridgemont High."

"Dude" also shows no signs of disappearing as more and more of our culture becomes youth-centered, said Mary Bucholtz, an associate professor of linguistics at the University of California, Santa Barbara.

"I have seen middle-aged men using 'dude' with each other," she said.