Definition of phi
: the 21st letter of the Greek alphabet — see alphabet table
Recent Examples of phi from the Web
Phi, to put it in numbers, is: Phi = φ = 1.61803398874989484820458683436563811772… and so on.
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Origin and Etymology of phi
Middle Greek, from Greek phei
First Known Use: 15th centurySee Words from the same year
Seen and Heard
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