UFO

American  

[yoo-ef-oh, yoo-foh] / ˈjuˈɛfˈoʊ, ˈju foʊ /

abbreviation

UFO's, plural UFOs plural

1. unidentified flying object: any unexplained moving object observed in the sky, especially one assumed by some observers to be of extraterrestrial origin.

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UFO British  

/ ˈjuːfəʊ /

abbreviation

1. unidentified flying object

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UFO ¹ Cultural  

1. The abbreviation for u nidentified f lying o bject. Sometimes referred to colloquially as “flying saucers.” Most UFO sightings have prosaic explanations; there is no hard evidence that extraterrestrial beings are visiting Earth.

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UFO ² Cultural  

1. An abbreviation for “U nidentified F lying O bject.” Often described as “flying saucers,” some UFOs are believed to come from other planets or galaxies and thus support the idea that human beings are not the only form of intelligent life in the universe. Few scientists agree.

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Usage

See UAP.

Etymology

Origin of UFO

First recorded 1950–55

Example Sentences

See Examples For:

UFO

So far, all but two of the UFO ETF’s top 10 holdings have seen their stock prices decline in June.

From MarketWatch ● Jun. 24, 2026

Cultural obsession with UFO conspiracies has renewed in recent years, bolstered by government initiatives and celebrity support.

From The Wall Street Journal ● Jun. 18, 2026

The incident prompted official investigations and has since become a cornerstone of UFO research in the UK.

From BBC ● Jun. 13, 2026

Meanwhile, earlier this spring, the U.S. government declassified another batch of UFO files and the response was roughly equivalent to a collective shrug.

From Los Angeles Times ● Jun. 11, 2026

We stood in the hallway, under a chandelier shaped like a sci-fi UFO, and the police began to grill me right there under its bright, blinking lights.

From "Confessions of a Murder Suspect" by James Patterson