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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The Where in the Woods UFO Stage will move into Centeroo. Melonee Hurt, USA Today, 18 July 2025 Overall, Dan Da Dan is a fun send-up of UFO and supernatural pop-culture, and also cements that with likeable leads. Ollie Barder, Forbes.com, 13 July 2025 The resulting mix of mystery and mass panic would spawn a worldwide craze, leading to countless UFO reports, hoaxes and sci-fi depictions. Mike Bezemek, Smithsonian Magazine, 10 July 2025 New York state has seen 66 reported Unidentified Aerial Phenomena (UAP) sightings during the first half of 2025, according to a report from the National UFO Reporting Center (NUFORC). Sarah Rumpf-Whitten, FOXNews.com, 7 July 2025 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

Browse Nearby Words

Cite this Entry

“UFO.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/UFO. Accessed 25 Jul. 2025.

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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