upside down

American  

adverb

1. with the upper part undermost.

2. in or into complete disorder; topsy-turvy.

   The burglars turned the house upside down.

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upside down British  

adjective

1. (usually postpositive; upside-down when prenominal) turned over completely; inverted

2. informal (upside-down when prenominal) confused; muddled; topsy-turvy

   an upside-down world

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adverb

1. in an inverted fashion

2. in a chaotic or crazy manner

Other Word Forms

• upside-down adjective
• upside-downness noun

Etymology

Origin of upside down

1300–50; re-formation ( upside ) of Middle English upsedoun, earlier up so doun ( up, so ¹, down ¹; sense of so obscure)

Example Sentences

The federal government has been promoting an upside down pyramid that features steak and cheese at the top, along with vegetables, to go along with its new dietary guidelines.

From The Wall Street Journal • Mar. 31, 2026

I also have a swing to go upside down on.

From Los Angeles Times • Mar. 20, 2026

She was working as an intensive care nurse when her life was turned upside down.

From BBC • Mar. 16, 2026

"In fact, we were also able to confirm that previous impressions were probably viewed upside down and back to front."

From Science Daily • Mar. 12, 2026

Roz found the flying machine upside down, with its landing gear poking above the rows of leafy plants.

From "The Wild Robot Escapes" by Peter Brown