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UFO

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noun \ˌyü-(ˌ)ef-ˈō\

Definition of UFO

plural

UFO's

or

UFOs

play \ˌyü-(ˌ)ef-ˈōz\

  1. :  an unidentified flying object; especially :  flying saucer

See UFO defined for English-language learners

See UFO defined for kids

From the M-W Editors

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Origin and Etymology of ufo

unidentified flying object

UFO Defined for English Language Learners

UFO

play
noun

Definition of UFO for English Language Learners

  • : a flying object in the sky that some people believe could be a spaceship from another planet

Learn More about ufo

  1. See words that rhyme with UFO Spanish Central: Translation of UFO Nglish: Translation of UFO for Spanish speakers Britannica English: Translation of UFO for Arabic speakers Britannica.com: Encyclopedia article about UFO

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