upside-down

Upside-down means turned so that the top is now at the bottom. Inverted, and usually by accident.

The hyphenated form goes before a noun, so an upside-down cake or an upside-down map, and the unhyphenated version follows a verb. An upside-down cake is baked with the fruit at the bottom and turned out. There is a figurative sense about disorder, since an upside-down world is one where nothing works as it should, and children's books are full of them.