upside down

adverb

1. with the upper part undermost.
2. in or into complete disorder; topsy-turvy: The burglars turned the house upside down.

adjective

1. (usually postpositive; upside-down when prenominal) turned over completely; inverted
2. (upside-down when prenominal) informal confused; muddled; topsy-turvyan upside-down world

adverb

3. in an inverted fashion
4. in a chaotic or crazy manner

late 15c., earlier upsadoun (late 14c.), up so down (c.1300); the so perhaps meaning “as if.”