UFO

noun

ˌyü-(ˌ)ef-ˈō 

ˈyü-(ˌ)fō

plural UFO's or UFOs ˌyü-(ˌ)ef-ˈōz 

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

Directed by Michael Mazzola, who previously helmed UFO documentaries like Close Encounters of the Fifth Kind and Unacknowledged, Plague of Corruption is currently only watchable by RSVPing for livestream events on the Amigo Film Studios website. —Wesley Stenzel, Entertainment Weekly, 12 Dec. 2025

Variety reported on a new UFO movie from Spielberg back in 2024, noting that the film will be a a reunion with Jurassic Park and War of the Worlds writer David Koepp. —Bethy Squires, Vulture, 11 Dec. 2025

The second edition will take place at UFO, Milan’s new cultural hub that houses Billboard Italy’s headquarters, which for the occasion will become the Women in Music House. —Billboard Italy, Billboard, 20 Nov. 2025

Some residents, like photographer Bo Bridges, decided to have some fun with the mystery by creating wine bottle labels featuring a UFO and submarine near the bubbling. —Matthew Rodriguez, CBS News, 19 Nov. 2025

Word History

Etymology

unidentified flying object

First Known Use

1952, in the meaning defined above

Rhymes for UFO

• acknow
• aglow
• ago
• airglow
• aloe
• altho
• although
• ammo
• backflow
• backhoe
• banjo
• barbeau

Kids Definition

UFO

noun

ˌyü-(ˌ)ef-ˈō 

plural UFO's or UFOs -ˈōz 

: an unidentified flying object

especially : flying saucer