unidentified aerial phenomenon

noun

plural unidentified aerial phenomena

: a mysterious flying object in the sky that is sometimes assumed to be a spaceship from another planet : UAP

—used especially as an alternative to UFO or unidentified flying object

Unidentified aerial phenomena (UAP), formerly referred to as UFOs, in theory, could include alien spacecraft, but the two aren't synonymous. The Defense Department's All-Domain Anomaly Resolution Office (AARO) considers a UAP "anything in space, in the air, on land, in the sea or under the sea that can't be identified and might pose a threat to U.S. military installations or operations."

—Urja Sinha et al.

Examples of unidentified aerial phenomenon in a Sentence

Recent Examples on the Web

The Defense Department Has Set Up a UFO Office The Pentagon has a new office dedicated to investigating and tracking UFOs—or unidentified aerial phenomena as they’re now known. —Brian Barrett, WIRED, 27 Nov. 2021

First, the preferred term is UAP, as in unidentified aerial phenomenon, and second, maybe! —Sara Netzley, EW.com, 1 Apr. 2024

Word History

First Known Use

1949, in the meaning defined above