Source : Webster's Revised Unabridged Dictionary (1913)

Dude \Dude\, n.
   A kind of dandy; especially, one characterized by an
   ultrafashionable style of dress and other affectations.
   [Recent]

         The social dude who affects English dress and English
         drawl.                                   --The
                                                  American.

Source : WordNet®

dude
     n : a man who is much concerned with his dress and appearance
         [syn: {dandy}, {fop}, {gallant}, {sheik}, {beau}, {swell},
          {fashion plate}, {clotheshorse}]