unidentified flying object
Definition from Wiktionary, the free dictionary
- Anything not readily explainable appearing to move through or be suspended in the air, primarily used to refer to objects that seem to be at least of small familiar aircraft size. Abbreviated UFO.
- The lights seen over the city last night, originally termed unidentified flying objects, turned out to be spotlights from a car dealership reflecting on low clouds.
- (colloquial) An alien spacecraft. More commonly called a UFO.
anything in the air not readily explainable
colloquial: an alien spacecraft