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

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

Word History

Etymology

unidentified flying object

First Known Use

1953, in the meaning defined above

Kids Definition

UFO

noun

ˌyü-(ˌ)ef-ˈō 

plural UFO's or UFOs -ˈōz 

: an unidentified flying object

especially : flying saucer