UFO: Meaning and Definition of

UFO

Pronunciation: (y'ef'ō' or, sometimes, y'fō), [key]
— pl. UFO's, UFOs.
  1. any unexplained moving object observed in the sky, esp. one assumed by some observers to be of extraterrestrial origin. Also calledCf.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
See also:
  • ufo (Thesaurus)