upside down
Americanadverb
-
with the upper part undermost.
-
in or into complete disorder; topsy-turvy.
The burglars turned the house upside down.
adjective
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(usually postpositive; upside-down when prenominal) turned over completely; inverted
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informal (upside-down when prenominal) confused; muddled; topsy-turvy
an upside-down world
adverb
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in an inverted fashion
-
in a chaotic or crazy manner
Other Word Forms
Derived Forms
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
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
She helps them recognize developmental moments, such as when a child turns a book upright on their own upon realizing it’s upside down, signaling letter recognition.
From Los Angeles Times • Jun. 8, 2026
The court heard that the defendants "life has been turned upside down".
From BBC • May 13, 2026
So far this year, the Iran war has turned OPEC’s usual production problem upside down.
From Barron's • Apr. 28, 2026
"The results are a surprise. They turn our understanding of the evolution of the eye and the brain upside down," says Dan-E Nilsson, professor emeritus in sensory biology at Lund University.
From Science Daily • Apr. 27, 2026
It was upside down, like a turtle flipped onto its back.
From "I Survived Hurricane Katrina, 2005" by Lauren Tarshis
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.
