UFO

A UFO is technically "unidentified flying object". Any object that flies and cannot initially be identified as an airplane, helicopter, blimp, balloon, kite or any other object that normally flies is a UFO. UFO is any real or apparent flying object that cannot be identified by the observer, especially those which remain unidentified after the investigation. UFOs have been spotted in many different places around the world. Many tens of thousands of UFO reports have since been made worldwide. But many sightings may yet remain unreported, due to fear of public ridicule because of the social stigmata surrounding the subject of UFOs, and because most nations lack any officially sanctioned authority to receive and evaluate UFO reports.

UFO
Unidentified Flying Object
Flying Saucer