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upside down

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See synonyms for: upside down / upside-down / upsidedown on Thesaurus.com

adverb

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

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Origin of upside down

1300–50; re-formation (see upside) of Middle English upsedoun, earlier up so doun (see up, so1, down1; sense of so obscure)
upside-down, adjectiveupside-downness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for upside down

upside down

adjective

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

adverb

in an inverted fashion
in a chaotic or crazy manner
upside-downness, noun
C16: variant, by folk etymology, of earlier upsodown
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
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