Definition of upside-down
: having the top at the bottom and the bottom at the top : placed so that the end that should be at the top is at the bottom <The sculpture looked like an upside-down pyramid.> <That flag is upside-down.>
UPSIDE–DOWN Defined for Kids
Definition of upside–down
1 : having the upper part underneath and the lower part on top <The letter "u" is an upside-down "n.">
2 : showing great confusion <upside-down logic>
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Thesaurus: All synonyms and antonyms for "upside-down"
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