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 ( see upside) of Middle English upsedoun, earlier up so doun ( see up, so ¹, down ¹; sense of so obscure)

Example Sentences

Among the memorable moments was the reunion of Bauhaus and singer Peter Murphy performing “Bela Lugosi’s Dead” while hanging upside down like a bat.

From Los Angeles Times • Apr. 6, 2026

I think she realized that you can keep playing it safe, and life can still end up completely upside down.

From The Wall Street Journal • Apr. 6, 2026

Our planet appears upside down, with the Sahara desert and the Iberian peninsula visible to the left and the eastern portion of South America to the right.

From BBC • Apr. 5, 2026

I also have a swing to go upside down on.

From Los Angeles Times • Mar. 20, 2026

The stone floors have been swept and chairs are resting upside down on tables.

From "The Bletchley Riddle" by Ruta Sepetys and Steve Sheinkin