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Synonyms

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.
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
"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adverb

  1. in an inverted fashion

  2. in a chaotic or crazy manner

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Unfortunately, the takeover battle was won just hours before the Iran war turned their financial worlds upside down.

From The Wall Street Journal • Mar. 20, 2026

Reece Lockett, said his life had been "turned upside down" and he had lost his parents, his partner and his job because of it.

From BBC • Mar. 14, 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

Allen, who represents the Palisades, said neighborhoods are being turned upside down by wildfires.

From Los Angeles Times • Mar. 4, 2026

He spun the water around the fish and easily turned it upside down.

From "Healer of the Water Monster" by Brian Young

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.