You hear about them on talk shows. You see them advertised at the mall. They target women, typically ages 18-45, and promise a new lifestyle through a change in wardrobe, hairstyle, and cosmetics. But a makeover doesn't have to be perpetuated by capitalist swine.

In general, a makeover is any remodeling job. You can make over¹ a project, a room, or a neighborhood. Most often, though, it does refer to the process of changing a person's appearance--presumably (although not always) for the better. For example:

"Sally and I are going to get makeovers at the salon today! I'm so excited, I could tinkle!"

"Boy, did you see that celebrity makeover? That bald guy sure did look like Britney Spears! Oh, what will MTV think of next?"

¹When used as a verb, the word is split. You cannot makeover something, but you can make something over.