Wiktionary
n. (context ufology English) A supposed observation, or observation of evidence, of extraterrestrial beings or their craft.
Wikipedia
In ufology, a close encounter is an event in which a person witnesses an unidentified flying object. This terminology and the system of classification behind it was started by astronomer and UFO researcher J. Allen Hynek, and was first suggested in his 1972 book The UFO Experience: A Scientific Inquiry. He introduced the first three kinds of encounters; more sub-types of close encounters were later added by others, but these additional categories are not universally accepted by UFO researchers, mainly because they depart from the scientific rigor that Hynek aimed to bring to ufology.
Sightings more than 500 feet (150 m) from the witness are classified as "Daylight Discs," "Nocturnal Lights," or "Radar/Visual Reports." Sightings within about 500 feet are subclassified as various types of "close encounters." Hynek and others argued that a claimed close encounter must occur within about 500 feet to greatly reduce or eliminate the possibility of misidentifying conventional aircraft or other known phenomena.
Hynek's scale became well known after being referenced in a 1977 film, Close Encounters of the Third Kind, which is named after the third level of the scale. Posters for the film recited the three levels of the scale, and Hynek himself makes a cameo appearance near the end of the film.
Usage examples of "close encounter".
Holly's only conscious expectation had been that a real close encounter of the third kind would be like nothing the novelists and screenwriters imagined in all their wildest flights of fantasy, because when referring to life from another world, alien meant alien, different, beyond easy comparison or comprehension.
He had come all this way to talk to a man who claimed to have experienced a close encounter with extraterrestrials.
Witnesses who were unlucky enough to have a close encounter with an unidentified flying object, usually a dazzlingly brilliant aerial light, are exposed to actinic rays .
Now it had only one remaining window, the side and rear panels were pocked with flechette strikes, the left rear quarter panel had been mostly torn off by a close encounter with a mortar track and the engine compartment was spurting steam.
Dana had one last look at the fortresses before they disappeared into battle clouds and smoke, a close encounter of the worst kind.
If Brian was killed, inadvertently or intentionally, during a close encounter, all of us in ufology must rethink our supposition that the extraterrestrials come in peace.
He must have had a close encounter with the ur'droch when it took the children out of her bedroom.