Short for “Sino Flying Object.” A quasi-symmetric (spherical,
cylindrical, octagonal, …) object that has recently been spotted (or finally been detected) crossing near “US sensitive sites”—a few of them were shot down by a
fighter jet because they allegedly or exaggeratedly posed a surveillance threat to the security of the country, or to the lives of
the people.
The US had shot three SFOs or UFOs in three days following the take down of a
Chinese spy balloon that floated their sky the previous weekend, but they themselves had hypocritically
launched no fewer than a dozen of these slow-moving spy or surveillance objects over the Chinese or Russian airspace since
last year.