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REFERENCE

UFO

n. countable
B1 Intermediate US //ˌjuˌɛˈfoʊ// ufo Informal

n. Stands for unidentified flying object. A strange object seen in the sky that people cannot explain or identify. You often hear this word when people talk about aliens or spaceships.

n. Abbreviation for unidentified flying object; any aerial phenomenon that cannot be readily identified or explained by the observer. Often associated with extraterrestrial hypotheses in popular culture.


SIMPLE

The pilot reported seeing a bright UFO over the desert.

CONTEXTUAL

Local residents gathered to watch the strange lights, convinced they had finally spotted a UFO.

COMPLEX

While most UFO sightings are eventually attributed to weather balloons or military aircraft, a small percentage of cases remain unexplained by conventional atmospheric science.

Origin

Abbreviations.

Usage

Usually pronounced as individual letters (U-F-O). Takes the article 'a' rather than 'an' because the first letter is pronounced with a consonant 'y' sound.

Pitfall

an UFOa UFOAlthough it starts with a vowel letter, UFO is pronounced starting with a 'y' sound (/ˌjuː.efˈoʊ/), so it requires the article 'a'.

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