John,
Here's what the word-detective has to say:
For a lightweight word denoting attention to fashion and a devotion to "cool," "dude" has proven remarkably durable. It first showed up in the late 19th century, most probably as a variation on "dud," a Victorian slang term meaning "article of clothing" (still heard today as "duds"). The original dudes were fops and dandies, well-to-do young men who were known for their fancy style of dressing as well as their often dissolute "lifestyles."
A few years later, "dude" made its debut in the Western United States as a disparaging term for any city-dwelling visitor (also known as a "city slicker") to cowboy country. The taming of the West brought a flood of tourists from the East, and "dude ranches" quickly sprang up to give the visitors a taste of "cowpoke life."
In the 1930's, "dude" mutated a bit and came to be used as a general synonym for "guy" or "fellow," without its former connotations of dandyism, and seemed to be slowly fading away. The early 1960's surfer culture of Southern California, however, gave "dude" a shot in the arm, transforming the word into one of its basic units of linguistic exchange. There were no "guys" or "fellows" hanging ten -- only "dudes."
After cruising through the 1960's and 70's as a low-level slang term, "dude" hit the big time again in the 1980's courtesy of the Teenage Mutant Ninja Turtles, and is still going strong today.
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My son practically lived TMNT, which I now realize
is probably why I use the term as much as I do!
Here is how to find the word-detective:
http://www.ipl.org/ref/QUE/PF/etymology.html
