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.