"Dude, where's my car?" The word is a staple of American slang. It means a man, a person, or a friend. It can be a noun or an interjection. It comes from the word "doodle," which meant a foolish person in the 1800s. It shifted to mean a city slicker, then a guy. By the 1980s, it was everywhere. Surfers said it. Teenagers said it. Now everyone says it.

Dude is gender-neutral in practice. "Dude" can address a woman. "We're all dudes" is a phrase from the movie Good Burger. It is casual, friendly, and slightly lazy. It is not a term of endearment like "darling." It is a term of camaraderie. It says, "You are one of us."

How to use it

• Greeting: Dude!
• Address: Dude, listen.
• Exclamation: Dude, no way.
• Noun: He's a cool dude.

Dude is not for formal settings. Do not call your boss dude. Do not call a judge dude. But in a group of friends, it is perfect. It is the Swiss Army knife of address. It fits almost anywhere casual. It is a small word with a big reach.