Dude (noun)

1. A man or boy; used as a friendly or casual way of addressing someone.
2. A man who is overly concerned with his appearance or clothes.

Origin:

Late 19th century (originally us): of uncertain origin; perhaps related to duds "clothes".

Examples:

1. Hey dude, what's up?
2. The dude in the suit looked out of place at the beach.
3. The surfer dude was hanging out near the water.
4. The dude was wearing designer sunglasses and a expensive watch.
5. The two dudes were laughing and having a good time.