The term "dude" has had different meanings throughout history and in different contexts. Here are some of the most common meanings:

• Dandy: From the 1870s to the 1960s, "dude" primarily meant a male person who dressed in an extremely fashionable manner, also known as a dandy.

• City dweller: In the American nineteenth century, "dude" was used to refer to a big city dweller unfamiliar with the ways of the Wild West. When such types came out West to enjoy the rugged life, they stayed in "dude ranches," basically resorts or spas, not real working ranches, and the term is still around today.

• Man: "Dude" is a slang greeting term between men, meaning "guy" or "man." It has been popularized by movies and TV shows, and has a distinctive whiff of American West Coast hippie culture to it.

• Fellow: "Dude" is also used as a general term of address used to a man, woman, or group.

• Unisex term: In the early 1960s, "dude" became prominent in surfer culture as a synonym of guy or fella. The female equivalent was "dudette" or "dudess," but these have both fallen into disuse and "dude" is now also used as a unisex term.

Overall, "dude" is a slang term that has evolved over time and has different meanings depending on the context in which it is used.