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

One Army recruiter recalled the only applicant who mentioned current events wanted to know whether recently released UFO videos were real. — Steven Beynon, ABC News, 17 Aug. 2026

By the end of our call, Michael Sheen is animatedly sharing stories of his family’s (potential) UFO sightings in south Wales. — Lily Ford, HollywoodReporter, 14 Aug. 2026

Hello Kitty mascotts are seen in a UFO Catcher machine in Osaka, Japan on March 25, 2026. — Jenny Lee, CNBC, 12 Aug. 2026

The latest document dump is part of an ongoing government effort to make UFO records public. — Terry Moseley, USA Today, 7 Aug. 2026

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