UFO

noun
\ ˌyü-(ˌ)ef-ˈō How to pronounce UFO (audio) , ˈyü-(ˌ)fō\
plural UFO's or UFOs\ ˌyü-​(ˌ)ef-​ˈōz How to pronounce UFOs (audio) , ˈyü-​(ˌ)fōz \

Definition of UFO

: an unidentified flying object especially : flying saucer

First Known Use of UFO

1953, in the meaning defined above

History and Etymology for UFO

unidentified flying object

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Dictionary Entries near UFO

Uele

Ufa

ufer

UFO

ufology

ufra disease

Uganda

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Time Traveler for UFO

The first known use of UFO was in 1953

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More Definitions for UFO

UFO

noun

English Language Learners Definition of UFO

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

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More from Merriam-Webster on UFO

Rhyming Dictionary: 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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