Definitions
the 21st letter of the Greek alphabet
Word origin
From Late Latin phi, from Ancient Greek φεῖ (pheî).
Used in a sentence
“The illusion of movement in a highway construction sign is an instance of the phi phenomenon, which is also at work in motion pictures and television.”
“Is it the phi phenomenon or the persistence of vision? Originally, the illusion of motion that movies excel at was thought to be the effect of the persistence of vision.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer2 curated clues
01“21st Greek letter”3 letters
02“Greek letter after upsilon”3 letters
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