\ ˈfī How to pronounce phi (audio) \

Definition of phi

: the 21st letter of the Greek alphabet — see Alphabet Table

Examples of phi in a Sentence

Recent Examples on the Web This term is called the Euler phi function after its inventor, the 18th-century mathematician Leonhard Euler. Quanta Magazine, "New Proof Settles How to Approximate Numbers Like Pi," 14 Aug. 2019 Other things that have zero phi, according to Tononi, include collectives of sentient individuals, such as corporations or the United States. Jason Pontin, WIRED, "How Do You Know You Are Reading This?," 2 Apr. 2018 CLE +250 LAL +275 BOS +700 HOU/SAS +1000 MIN +1400 PHI +1600 MIA +2500 GSW +2800 — OddsShark (@OddsShark) August 17, 2017 3. Charles Curtis, USA TODAY, "Why the Cavaliers aren't trading LeBron James," 18 Aug. 2017 Phi, to put it in numbers, is: Phi = φ = 1.61803398874989484820458683436563811772… and so on. Curtis Silver, WIRED, "The Sound of Phi (the Golden Ratio)," 18 June 2012

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'phi.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of phi

15th century, in the meaning defined above

History and Etymology for phi

Middle Greek, from Greek phei

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Time Traveler for phi

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The first known use of phi was in the 15th century

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Statistics for phi

Cite this Entry

“Phi.” Dictionary, Merriam-Webster, Accessed 10 Jul. 2020.

More from Merriam-Webster on phi

Rhyming Dictionary: Words that rhyme with phi Encyclopedia article about phi

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