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
: a mysterious flying object in the sky that is sometimes assumed to be a spaceship from another planet : 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

called also UAP, unidentified aerial phenomenon, unidentified anomalous phenomenon

Examples of UFO in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
The General is after Brock, unaware that Brock is coming to him, having caught a lift to nearby Las Vegas from Martin (Ifans) — a conspiracy theorist and UFO nut — who is driving his family in a camper van to Area 51, hoping to catch a glimpse of it before it’s gone for good. Damon Wise, Deadline, 23 Oct. 2024 Roswell is a city of about 48,000 residents and is famous for the alleged crash of a UFO in 1947. Julia Gomez, USA TODAY, 21 Oct. 2024 Their profession takes a turn when a mysterious UFO starts looming above their family's ranch. Killian Baarlaer, The Courier-Journal, 13 Oct. 2024 The console’s maker, UFO Soft, also developed these games. PCMAG, 12 Oct. 2024 See all Example Sentences for UFO 

Word History

Etymology

unidentified flying object

First Known Use

1953, in the meaning defined above

Time Traveler
The first known use of UFO was in 1953

Dictionary Entries Near UFO

Cite this Entry

“UFO.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/UFO. Accessed 19 Nov. 2024.

Kids Definition

plural UFO's or UFOs -ˈōz How to pronounce UFO (audio)
: an unidentified flying object
especially : flying saucer

More from Merriam-Webster on UFO

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