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UFO

noun \ ˌyü-(ˌ)ef-ˈō \

Definition of UFO

plural UFO's or UFOs play \ˌyü-(ˌ)ef-ˈōz\
: an unidentified flying object; especially : flying saucer

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Origin and Etymology of ufo

unidentified flying object

UFO Defined for English Language Learners

UFO

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

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