Meaning

• A man, generally a younger man.

  "So we were at the mall and these two dudes just walk up to us and say "hi"."

• (used in the vocative) A term of address for someone, typically a man, particularly when cautioning him or offering him advice.

  "Dude, I'd be careful around the principal; he's having a bad day."

• An inexperienced cowboy.

• A tourist.

• A man who is very concerned about his dress and appearance; a dandy, a fop.

Meaning

• To address someone as dude.

• To take a vacation in a dude ranch.

• Usually followed by up: to dress up, to wear smart or special clothes.

Meaning

• A term of address, usually for a man, conveying awe, excitement, surprise, etc.

  "Dude! You finally called!"