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 UFO (audio) , ˈyü-​(ˌ)fōz \

Definition of UFO

: unidentified flying object "All right." The President sighed. "Is there anybody around this table who thinks UFOs and this signal from Vega have anything to do with each other?"— Carl Sagan In 1966, the first UFO "abduction" was described in journalist John G. Fuller's book The Interrupted Journey.— Keay Davidson

First Known Use of UFO

1953, in the meaning defined above

History and Etymology for UFO

unidentified flying object

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Cite this Entry

“UFO.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/UFO. Accessed 24 Jan. 2021.

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More Definitions for UFO

UFO

noun
How to pronounce UFO (audio)

English Language Learners Definition of UFO

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

More from Merriam-Webster on UFO

Nglish: Translation of UFO for Spanish Speakers

Britannica English: Translation of UFO for Arabic Speakers

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